This story originally aired Dateline NBC on July 7, 2008.
They are lured by turquoise waters, the stunning kaleidoscopes of sea life, and the addictive tranquility of exploring it all.
Richard Neely: I've never seen anything so fantastic, so beautiful.
Matt Lauer: How would you describe the role it plays in your life right now?
Ally Dalton: Uh - it is my life right now.
Ally Dalton, 40, and Rich Neely, 38, share a deep affection for diving. Five years ago, Rich ditched his career as a cabinet maker in Britain to become a dive instructor in Thailand.
Richard Neely: I was looking for a change in my life and somebody passed me an open-water diver manual. And I thought "Wow. I have to do this."
Matt Lauer: It was an epiphany?
Richard Neely: Absolutely. And I was hooked.
Ally owns a successful pub and restaurant in Sacramento, California, but after taking a dive vacation to Thailand last year - and meeting Rich - a casual hobby became her passion.
Ally Dalton: Decided last year to get my dive master certification, which is a professional level status and I've spent the last eight months mostly diving, working in the diving industry.
Matt Lauer: With wrinkled fingers? (Laugh)
Ally Dalton: Yeah. Pruned fingers. Very different to what I'm used to in the restaurant business.
In May, the couple planned a scuba trip to Indonesia’s Komodo Island. On the way, they stopped to visit family and friends in Australia -- where the Great Barrier Reef, a diver's nirvana, was too tantalizing to resist.
Ally Dalton: We said "How can we not go diving on the Great Barrier Reef when we're so close?"
Ally and Rich booked a 3-day excursion on this catamaran, called "Pacific Star." It would take them from Airlie Beach, to the Whitsundays - 74 islands in the heart of the Great Barrier Reef - and then to the pristine waters of Bait Reef.
Matt Lauer: This trip, when you looked at it on paper, even though it was somewhat spontaneous, this is not a death-defying, thrill-seeking, adventure-laden journey. This is a chance to blow off a little steam and have some fun.
Rich Neely: Absolutely.
Ally Dalton: Absolutely.
But what should have been a relaxing, scenic tour of this underwater Eden would become a terrifying nightmare, one eerily similar to the movie "Open Water."
It began uneventfully enough. At 7 p.m. on Wednesday, May 21, the couple boarded the boat, which was manned by a skipper and three crew members. Among the 20 passengers, Ally and Rich were easily the most advanced divers, especially Rich -- a master trainer with 2,600 dives under his belt.
Matt Lauer: If you're a dive instructor and a dive tour operator, are you a 10 on a scale of 1 to 10, or does anybody ever get to be a 10?
Rich Neely: I feel 100 percent confident and comfortable, that must be a 10. I'm a big hulk of stainless steel and rubber hoses and black neoprene, I guess. And the fish must laugh at me, but I feel 100 percent comfortable.
On Thursday, the Pacific Star moored at Whitehaven Beach. Ally and Rich photographed themselves marveling at the white, silica sands. But they were most content below the surface, turning their camera on all the magnificent fish -- and sharks.
Ally Dalton: We had seen sharks on every dive.
Matt Lauer: What kind of sharks did you see?
Rich Neely: Small reef sharks about four, five feet, maybe six feet a couple of them. Small.
Matt Lauer: So first couple of days of this trip seem pretty routine. Couple of nice dives.
Rich Neely: Yeah.
Ally Dalton: A-huh.
Matt Lauer: Saw a couple of sharks.
Rich Neely: We read a book. We laid in the sun. We watched the horizon.
On Friday, May 23, the couple took two morning dives, and planned another two after lunch. To squeeze in the fourth, they needed to stick to a tight schedule.
Ally Dalton: We had to be in the water by 2, out by 3. You have to be out of the water for a surface interval before you get back in the water again. So that meant we'd be out by 3, back in the water by 4:30.
Matt Lauer: Because by 5:30 in this area, the sun's going to start to go down.
Ally & Rich Neely: Exactly.
Matt Lauer: And you'll lose daylight.
Ally Dalton: Right.
Matt Lauer: Most people in dive circles know that generally when a dive begins, there are instructions given out by whoever's running the dive. What were you told?
Rich Neely: From the tour leader, we were told that we would be doing a dive at Paradise Lagoon. That was pretty much it.
Matt Lauer: Did that tour leader tell you "Here's where you can go. Here's where you can't go. Here's the distance from the boat you can travel. Don't go anything above that?"
Rich Neely: Not at all. The only part of that was here is where you should go.
Matt Lauer: So, "make sure you see this."
Rich Neely: Yes.
Ally Dalton: He actually specified a particular marker to look for, which was through the passage and out of the lagoon.
Matt Lauer: But the one rule you guys did know, one hour.
Rich Neely: Yes.
Matt Lauer: Surface after one hour and if after that hour, you did not return to the boat, someone from the boat would come get you.
Rich Neely: Exactly.
Matt Lauer: How would they come get you, in a dinghy-
Rich Neely: They pick us up in a dinghy.
Matt Lauer: Tanks are full. Your gear is ready. You slip into the water. What are the seas like?
Ally Dalton: Pretty calm.
Rich Neely: Yeah.
It was a perfect dive - they snapped photos of unusual fish, even this group of sharks.
Rich Neely: A group of seven sharks together.
Ally Dalton: Gray reef sharks.
Rich Neely: For several minutes, very close to us, which was great.
Matt Lauer: A few minutes before 3, the hour up, Rich did something he always does at the end of a dive - inflating a buoy like this one to signal the boat that they were preparing to surface.
Rich Neely: It has six meters of string with a small stainless steel weight on the bottom. Inflate it with air and it shoots to the surface.
Matt Lauer: Up the string you go, You reach the surface. What's the first thing you remember seeing? Was everything fine?
Rich Neely: Everything's fine. We can see the boat. And we can see the yellow dinghy returning to the boat.
Matt Lauer: So all is at it should be?
Rich Neely: Absolutely.
But not for long. Ally and Rich were in danger, their perfect dive about to become a descent into terror.
Matt Lauer: Did you make the attempt now to swim your way back to the boat?
Rich Neely: We realized that we couldn't swim back to the boat, we realized the waves, the wind is coming towards us.
Matt Lauer: But so no biggie. You'll just sit there, and you'll wait for that yellow dingy to—
Rich Neely: Yeah. They know we're coming up at 3 o'clock, and they just picked two other divers up.
Ally Dalton: My first hint of worry was when the dinghy driver got off the dinghy and went up the stairs back onto the boat, because I thought "Well that's strange." I joked that she's probably having a cigarette and then when she didn't come back down, you know no-one was getting back on the dinghy.
The minutes ticked by. 3:10, 3:15, 3:20. And, they say, the current picked up - pushing them away from the boat.
Matt Lauer: Some people who maybe don't understand what it's like in the water or understand diving might say, "Well, at that point, whether you think it would be hard or not, I'd start swimming for that boat. Even against the current. Even against the waves." Was that an option?
Rich Neely: We tried, didn't we?
Ally Dalton: We did.
Rich Neely: Within, what, five, 10 minutes, we'd realized that even if we wanted to swim very, very hard, we would use up too much energy, so we'd have to stop and drift back again. The waves were then picking up. Wind was then picking up. Our small legs were just not powerful enough.
Matt Lauer: At this point, should someone on the boat be worried, counting heads? It was an hour dive, and we have two people who aren't back yet?
Rich & Ally Dalton: Yeah. Absolutely. Because we were the first ones in the water.
Matt Lauer: But you're looking at the boat, and you don't see anyone with binoculars. You don't see people running back and forth business as usual on the boat?
Rich & Ally Dalton: Yeah.
Why didn't anyone notice them? Rich had already inflated his 4 foot long marker buoy, which should be visible a mile away.
Rich Neely: All the time, I'm holding above my head the surface marker buoy to make as big a visual triangle as possible. And we are both shouting. I'm whistling. Ally's waving her arms.
Ally Dalton: I'm getting angry. I'm pissed off and I'm thinking about "When I get back on that boat, I am going to chew these people out," because, such disregard. "How can they not be coming to pick us up?"
It was 4 p.m. A full hour had passed. Rich pulled out the small waterproof camera he always carries on dives.
Rich Neely: I just took a picture of the sea state I wanted to document it. I knew that whatever happened, even if they picked us up before sunset we've got complaints to make about this - this is dangerous.
The couple's life jackets kept them afloat, but they say their dive expertise was no match for the powerful current. They were rapidly being pushed out into the vast Pacific Ocean.
Ally Dalton: Even though we're getting further away, we can still clearly see that the boat hasn't moved. It's moored, so you can see that it's holding fast in one set position.
It wasn't until 4:15 - 75 minutes after they surfaced from their dive - that Ally and Rich say there was noticeable activity on the boat's top deck.
Rich Neely: "Are they looking for us? Are they looking for us? They must be. Look. Look. Look."
The Pacific Star was on the move. Finally, it appeared a search was on. But the boat didn't come anywhere near them -- and by 5:30, it had anchored again. Ally and Rich were gripped by fear. After all, these are shark waters. And, there's that terrifying movie.
"Open Water" is based on the true story of Americans Eileen and Tom Longergan, who were left behind by a dive boat on the Great Barrier Reef 10 years ago, and never seen again.
Matt Lauer: You had seen the movie and you start to think about it, but you didn't say anything to Ally?
Rich Neely: No. I want to talk to Ally about it, but at the same time, I don't potentially want to make it worse by mentioning the movie, which instantly is going to make Ally think about sharks.
Matt Lauer: By this time, Ally, had you been thinking about sharks?
Ally Dalton: Before then I had been thinking about sharks.
Matt Lauer: But you didn't say anything to Rich either?
Ally Dalton: No, for probably the same reasons.
If they were too scared to say the "s" word out loud, other dangers were all too apparent.During their dive, the water temperature had been 75 degrees. Now, as Rich took this photo of Ally, darkness was setting in, the waves were swelling, and even in wetsuits, the couple was shivering.
Rich Neely: The wind felt biting cold.
Matt Lauer: How cold were you, Ally?
Ally Dalton: I actually find myself shaking right now when you start talking about it because as the wind blew and hit my head, I could feel myself losing even more body temperature.
It's dusk, the weather is disintegrating. It seems that about this time, anger gives way to a sense of "We've got to survive."
Rich Neely: I know that we're probably now going to be in this for the duration of darkness, and there's wind. There's waves. First thing I've got to do is keep us in contact all night, physical contact.
Matt Lauer: And possibly prepare for the long haul?
Rich Neely: Yeah.
Matt Lauer: To make themselves more buoyant and conserve energy, they dumped their weight belts and air tanks. Then, using his diver's knife, Rich cut off ten feet of rope attached to his marker buoy, and tied himself to Ally.
Rich Neely: I knew that throughout the night we would never be more than 3 meters apart. And we could also pull each other together if we were taken apart by the waves.
Matt Lauer: Can you both just describe for me the emotions of the sun going down? Of darkness settling in?
Rich Neely: For me, it was resignation.
Ally Dalton: For me, it was terror. It's bad enough being out there on the open ocean and no-one coming for you. But to be out there in the dark, I didn't think I could make it through the night.
Ally Dalton: I got very panicky. And Rich came right up to me and you know, we have the buoyancy jackets on, and grabbed the jacket, and looked me in the eye. And he said "We're going to get through this. You've got to be stronger than you've ever been before. But we will get through this."
Matt Lauer: Their nightmare on the open seas was just beginning.
Matt Lauer: The waves are now between two and three meters. We're talking between six and 10 feet high.
Rich Neely: Yeah.
Matt Lauer: That's big waves.
Rich Neely: Yeah. Big waves. And we're watching them come as a wall of water. Maybe three or four waves would come past and then a smaller one would just come and slap you in the face—
Ally Dalton: Smack you in the face.
Rich Neely: Very hard. We were pretty angry. We were shouting at the waves. (laughter) And-- "Why? What did we do to deserve that one? Thank you very much."
Ally Dalton: As the waves were getting bigger, we put our masks on so that it actually added a little bit of warmth because it protected our face.
At 7:15, as they battled the relentless seas, Rich took this photo of Ally - and this one of himself.
Rich Neely: I wanted people to see this and know that we look wet, cold, angry, miserable.
Ally Dalton: Terrified.
Rich Neely: Terrified.
In the piercing cold, the couple clung together, desperate for warmth.
Rich Neely: Ally's shivering - a lot more than me. I'm feeling guilty because I've got a 7-millimeter wetsuit, and Ally's got a 5-millimeter wetsuit.
Matt Lauer: Yours is a lot warmer than hers is?
Rich Neely: Yeah.
Matt Lauer: Thicker.
Rich Neely: Thicker. I know Ally's very, very distressed, so we pulled each other together, wrapped our legs around each other, pushed our stomachs together. I didn't know if it would work or not, if the warmth would transfer through the neoprene, but it did, didn't it?
Ally Dalton: U-huh, helped a lot.
Rich Neely: We said, "Hey, hey, can you feel? Can you feel the warmth?" "Yeah, I can."
Matt Lauer: You think it was a physical warmth, or more of an emotional warmth? Kind of nice to have that support?
Ally Dalton: Both. It allowed me to look at him. And just that closeness gave me a sense of protection.
But waiting in the angry waves was agonizing. At 8, five hours after they were due back on board, Ally and Rich could still see their tour boat on the horizon.
Rich Neely: Even when it was dark, we could still see the boat. We could see the mast lights.
Where were the rescue choppers? The search lights? Rich got nervous - was huddling for warmth too risky?
Rich Neely: While we were doing this, we were motionless. The current and the waves were taking us away from the boat. I didn't want to drift any further away from that point than we had to, so after perhaps 30 minutes of sharing heat, I'd say "Hey, we need to move. Can we do it? Can you do it?" So we'd then lay on our backs and we were kicking our feet. At least to try and maintain some kind of position in the water.
By 9, they were in a fierce - yet delicate - battle for survival, huddling every half hour for warmth, then gently kicking on their backs. But now Ally was worried -- recalling something she'd just read in this book.
Ally Dalton: It described the stages - progression of hypothermia and if you exercise, that's actually not good because then your body has to send blood to the muscles away from your core, and your organs. And so I knew it was in a way counterproductive.
Matt Lauer: By this point, you're really thinking "I'm in serious trouble here."
Ally Dalton: Oh, without a doubt. And for me, it was worse, because I started vomiting in the water - with nothing to bring up. And it was incredibly painful. My stomach muscles and my chest muscles were so tight.
Rich Neely: It was really bad for me. I couldn't help her. I just had to watch.
Matt Lauer: Then, at 9:30, they got their first glimpse of hope.
Rich Neely: "There's a light. There's a - it's a helicopter! And my instant thought was "Oh, thank you."
Ally Dalton: We did. We thought, "Okay, it's going to be okay."
Rich Neely: Oh wow. Yeah.
Ally Dalton: There was that huge sense of relief that they're looking and they're going to start the search and they're going to find us.
Matt Lauer: Was the helicopter flying in a search pattern? Flying straight?
Ally Dalton: It started about where we could see the lights on the boat. And we could see it circling. And it was progressively getting to be a bigger circle.
Matt Lauer: Frantically, Rich began flashing his camera in the chopper's direction, signaling for help.
Rich Neely: Every time we saw what appeared to be the helicopter on its expanding circle head towards us, I'd flash once and then hold it up again and flash again. And I got off maybe 5 flashes per trip.
Matt Lauer: Did you think they were going to see that? I mean –
Rich Neely: I really did. I expected to flash and see the helicopter suddenly change course and come straight towards us.
Ally Dalton: And then we would see it turn away - it wasn't coming anywhere near us.
Matt Lauer: The sight of watching it disappear –
Rich Neely: (Ally sighs) Not pleasant.
Matt Lauer: For hours, the choppers came and went, and every time they did, Rich continued to flash, his camera recording endless pictures of the black sky.
Rich Neely: Maybe 100, 110 pictures.
Matt Lauer: Of the darkness?
Rich Neely: Of the darkness, yeah.
By 11:30, there were fewer and fewer helicopters visible. Was the search being abandoned? Ally and Rich had been lost at sea for eight and a half hours.
Matt Lauer: Still, at this point, the S word never mentioned between the two of you?
Ally Dalton: I didn't want to bring up sharks. I was thinking about it. I was menstruating. And being in the water that long, I knew that I was bleeding. And it - "I'm shark bait" is what I'm thinking.
Rich Neely: I was thinking about this. "Okay are we going to be bitten by sharks. Am I going to feel, from the movie, "What is that just bumped on my leg?"
Rich Neely: No, no. We'll be okay. We're covered in neoprene. There's no skin. And we're not bleeding anyway- we're not bleeding - oh no. And then I remembered that it was Allie's time of the month. And I had to put it out of my head. I knew there's nothing we can do to prevent a shark being inquisitive. And I just had to convince myself, "That can't happen. We've got to be lucky."
Rich Neely: We were feeling extremely low.
It was midnight. Ally and Rich had been adrift on the Great Barrier Reef for nine hours, six of them in the dark -- and Ally's resolve was fading.
Rich Neely: Whenever Ally went quiet, I would pull her in, or if I didn't pull her, I would shout "Are you okay?" And if I got a very quiet "Yeah, " I would shout again until I got a louder response.
Pulling on the 10 feet of rope that was keeping them connected, entwining his legs around hers, Rich urged Ally not to give up.
Ally Dalton: I think that's when he became strong for me. At some point I made a conscious effort to just say "OK, get through the next 30 minutes. Just 30 more minutes. 30 more minutes."
On the black, open ocean, an eerie sense of isolation was closing in.
Matt Lauer: These helicopters that had been a fairly frequent presence in the area, flying in that familiar search pattern, started to see fewer and fewer of them?
Rich Neely: Yeah.
Ally Dalton: They actually came not too far from us but then the pattern changed, and it was gone.
They were alone, surrounded by nothing but dark seas and black sky. Ally and Rich were about to face their most harrowing hours.
Matt Lauer: About midnight, while Ally has already clearly started to exhibit some of the signs of hypothermia, you start to recognize them in yourself as well?
Rich Neely: Yeah, I start shivering then.
Matt Lauer: Uncontrollably.
Rich Neely: Yeah. I couldn't stop it. I feel myself shivering, could feel my chin like this and I was shivering here, in my midsection as well. That started to worry me now, that we wouldn't be able to keep enough heat between us.
Matt Lauer: Did you think you were going to be okay at that point?
Rich Neely: I didn't know if I was going to be okay. I didn't know if Ally was going to be okay. But, I knew that we had to believe we would be.
Between the shivering, and Ally's violent stomach spasms, the couple was weak, exhaustion taking over. Even in the turbulent water, Ally began slipping into a hazy sleep.
Rich Neely: It was because of our physical deterioration. And you realize that a human being can only take so much physical deterioration, before, ultimately, we die. We were aware of that, and I made sure that Ally shouted to me. Ally woke up. And you did, didn't you?
Ally Dalton: Yeah.
Matt Lauer: Ally, by this point have you thought about "Am I going to die out here tonight?"
Ally Dalton: Oh yeah.
Matt Lauer: And you said "I love you" over and over again?
Rich Neely: (pause, nods, looking at Ally)
Matt Lauer: Why did "I love you" feel so good?
Ally Dalton: It gave me that reminder that someone really wanted me to make it through this, because I was really questioning whether I could. And he wasn't going to let me go.
Love was willing them to remain strong, but by 2 a.m. - 11 arduous hours into their ordeal, Ally and Rich were losing it.
Matt Lauer: Both of you, not on cue, but close to the same time, start to hallucinate.
Ally Dalton: I'm looking up at the sky just trying to wrap my head around what's happening suddenly the sky was a reef. And I'm looking at sand, and corals, and I can see a barracuda
Matt Lauer: So it's a world upside down?
Ally Dalton: Exactly. It felt like I was diving upside down - but on steroids.
Rich Neely: I saw a very huge lady's head and shoulders. She had her knuckles on the cloud, looking down at me, with a young boy next to her. I stopped myself, "Whoa, I'm hallucinating." This is going on for hours.
Ally Dalton: And then I started saying things to Rich that made no sense.
Matt Lauer: The shivering, the waves, the weather, the hallucinations, gibberish - so the "I love yous" and the "We're going to get through this" had stopped by that point?
Rich Neely: By then, I was calling to Ally "You OK?" That was all I could manage.
At 3 a.m. - 12 hours after they should have been safely back on board the Pacific Star, the distant buzz of helicopters ceased all together. At 4, the lights on the boat vanished from view, no longer a tiny, but reassuring, glow. Rich hit bottom.
Matt Lauer: You've been taking these photographs throughout the night. And now you start to think, although I don't think you mentioned it to Ally, of perhaps using your camera to record something else?
Rich Neely: I'm not sure if I can make it. I'm thinking "Is this really the time that I am meant to die?" If it is, how terrible for my dad. How are they going to find out? They've never been to my house in Thailand. What about all my things? How is all of this going to get sorted out? What do I do?
Matt Lauer: So you were going to sit there in the water in the midst of this ordeal and start recording a last will?
Rich Neely: I want to talk into the camera and say "Dad, my email address is such and such, The address is this. My landlord's name is this." Blah blah blah blah.
Matt Lauer: Why didn't you do it?
Rich Neely: I kept putting it - survival's more important. I've got to keep going. This - it can't happen. It can't happen. The sun's coming up soon. It's getting closer to sunrise, I'll put if off.
Matt Lauer: Rich knew that with the sun, rescue planes might return. But dawn would also bring sharks to the surface, looking to feed.
At 5:30 a.m. Saturday, 14 and a half nightmarish hours into Ally and Rich's ordeal, hints of light finally broke the darkness on the Great Barrier Reef.
Matt Lauer: Dawn means the night is over. Maybe the search can begin again. But you in particular start to think about what you know about sharks?
Rich Neely: Yeah. All of the guests on the boat that I work on, they all want to see sharks. And the best time to see them is sunrise diving, as early as possible. So I know that once it comes up and there's a light above us, we're silhouettes on the surface. There's me. Ally next to me. Black wetsuits. Again, don't think about it. Put it out of your head.
Matt Lauer: And don't talk about it.
Rich Neely: And don't talk about it.
Matt Lauer: How long did this night seem? How long did it feel?
Ally Dalton: An eternity.
Rich Neely: It did, yeah.
Across the choppy seas - some 7 or 8 miles away - it had also been a trying night for the 18 distraught passengers still on board the Pacific Star.
Rachel Hauser: I woke up maybe 15 or 20 times. I could hear the noise from the helicopter and every time we're thinking "Did they find them, did they find them?"
Mikey Paton: No one really slept that night.
Michael Paton was chronicling the tense evening in his travel journal.
Michael reading: "Ally and Rich were still missing, and the boat had reached a state of panic."
On the boat, it had been 14 and a half hours of fear and confusion.
On Friday afternoon, 4 divers had followed Ally and Rich into the water. Those divers were safely picked up by the dinghy, but had returned with a warning about the surprisingly fierce currents.
Rachel Hauser: Saying that the currents had been quite strong underneath. And they felt they were pulled - quite strongly by it.
That was shortly after 3'oclock. Everyone knew Ally and Rich should already be back - but no-one seemed concerned.
Mikey Jones: It didn't occur to us that they wouldn't come back.
Matt Lauer: In fact, things were so relaxed, these boys plunged in for a dive.
Mikey Jones: We didn't appreciate how severe it was that they hadn't surfaced in the agreed time. We were just like "Oh, they're 5 minutes late, you know, it's not such a big deal." So, we just jumped in really.
Michael reading diary: "Mikey and Mark entered the water, returning around 45 minutes later. They'd been caught in the current though they were quite lucky and still managed to return to the boat safely."
The boys had barely managed to out-swim the currents. By the time they climbed back on board, Ally and Rich were an hour overdue. It was only then, the passengers say, that the crew realized something was terribly wrong. The dive instructor was frantic.
Rachel Hauser: We started to really freak out and realize something was really up - and bad, you know, he thought by that time they would be on the boat
Matt Lauer: Everyone rushed to the top deck to help the crew scan the seas.
Michael reading diary: "All of the passengers were on the roof with all available sets of binoculars trying to spot anything floating in the water."
Mikey Jones: "Whoa, is that them? Is that them? And it wasn't them."
The Pacific Star ran up and down the lagoon, but there was no sign of Ally and Rich. And at sunset, when the waves swelled, the boat was forced to stop moving.
Rachel Hauser: The storm was pretty bad. The skipper said he didn't want to put our lives at risk, and we're going to moor at the buoy for the night and wait for the rescue.
None of the passengers Dateline spoke to is certain what time the call was placed to alert authorities, but many found the wait for help unnerving.
Xavier Zen-Ruffinen: It was quite late. We're also trying to listen for planes or helicopters. And saying "that's weird," because no rescue is here to try and locate them.
Michael reading diary: "At this point, all of the crew were visibly shaken. Most of the passengers were in the saloon, trying and failing not to think about what was going on."
While the passengers made futile attempts to distract themselves, the panicked dive instructor dove into the black water.
Michael reading diary: "Kylie was going to dive into the lagoon to try and look for them underwater."
Xavier Zen-Ruffinen: He was really stressed, panicking, taking all his stuff. And he went into the small boat, the dinghy.
Rachel Hauser: He started to dive basically in the middle of nowhere, in the middle of the night.
Michael reading diary: "Kylie returned from the dive with no results. At this point, the helicopter arrived, and began searching with large spotlights."
Around 2 a.m., the water police boarded to question the passengers and crew. By morning, a somber mood had set in.
Mikey Jones It was really sort of sad and low.
Michael reading diary: "And hope of a happy ending was rapidly fading on the boat."
As the subdued passengers wondered if ally and rich had survived the night, the rescuers trying to find them were feeling just as skeptical.
Patrick Martin: They're out in the deep ocean, miles and miles away from land, and the chances of picking them up in the water were quite remote.
Matt Lauer: Three aircraft, including two choppers equipped with infrared cameras that sense heat, had searched much of the night, covering nearly 63 square nautical miles north of the lagoon -- but found nothing.
At 5 a.m., John Chate and Patrick Martin went up in this chopper, one of 10 aircraft that launched an intensified daylight search.
John Chate: There's not much we can do overnight. If we'd got the call before sundown, we may have been able to get out and find them.
Their job was painstaking. In the midst of the vast ocean, Ally and Rich would be easy to miss.
Patrick Martin: You're looking for a surface area the size of say a basketball which would sort of represent somebody's head. You're only going to catch that in a quick glance. And the greatest fear I have is, what if we've flown over the two divers in the water and we've missed them?
Ally and Rich feared the very same thing. By 8 a.m., Rich was taking photos of one plane after another circling above ... but it had been 18 hours -- and the couple had little faith that anyone would ever find them.
Ally Dalton: We were really at our lowest, lowest point. One helicopter in particular came very close to us. And we thought, "If he can't see us, they're never going to see us." And we were discussing "How can we make it through another day?" Because we knew we couldn't make it through another night, for certain.
Matt Lauer: And then you see the plane -
Finally, someone knew where they were. But as the plane was approaching, so was a deadly sea creature.
It was 8:30 a.m. They’d been in the water for 18 and a half hours, and for the first time, Ally and Rich were sure they were going to survive.
Ally Dalton: Oh my God, they've seen us, they've seen us. We're going to be OK. And I'm blowing kisses at him because I'm just so, I'm saying "Thank you, thank you."
Rich Neely: And all the time I've got the sausage in the air. And as they're spinning, we're spinning around with them.
Matt Lauer: You don't want to lose eye contact?
Rich Neely: No, yeah. (laughter)
Matt Lauer: Was there any discussion about who would get in that helicopter first?
Rich Neely: No. It's an unspoken rule.
Matt Lauer: Yeah, right.
Ally Dalton: When the rescue helicopter came and opened up the door, I immediately had my dive knife, cutting the cord. (laughter)
Matt Lauer: It's been nice - enjoy your day!
But just as the chopper was preparing to winch Ally out of the ocean, something ominous appeared in the water.
Patrick Martin: I was at the door when we saw the snake. And I think I just froze.
Matt Lauer: It was a sea snake - a creature with venom so potent it can cause paralysis, and even death.
John Chate: Quite a large sea snake made a beeline straight for her. And I thought "Oh no, here we go. We’re going to have some medical complications to this rescue."
Matt Lauer: Here you've survived the elements, the waves, the hunger, the thirst, everything, and here comes one of these poisonous snakes.
Ally Dalton: He actually lifted his head right into my face. The helicopter actually lifted back up, lifted away from us because it saw the snake. Fortunately, it slithered away. Thankfully, because they are incredibly poisonous.
Matt Lauer: With the snake out of sight, Patrick Martin was lowered down to pluck ally to safety.
Patrick Martin: Halfway down, I could see a big, beaming smile on Ally's face. As I got closer to her in the water, and put the rescue strap around her, she was just like "I feel like giving you a big kiss right now."
On board the Pacific Star, word that Ally and Rich were still alive prompted resounding cheers.
Mark Douthwaite: There was a shout from Kylie because he was on the radio. And we just heard him scream.
Rachel Hauser: We felt so relieved and so happy for them.
Matt Lauer: By 9 a.m. Saturday, Ally and Rich's 19 hours of watery hell were officially over. They had drifted nine miles from the lagoon where they set out for their dive, and now, their rescuers marveled at their luck.
Patrick Martin: Two divers were found in - literally, in the middle of nowhere. Amazing. Absolutely amazing.
Just as amazing: The couple needed only brief treatment for exhaustion and dehydration. They had survived their ocean drama remarkably well.
The miraculous story circulated quickly, only to take a rapid turn. The pair accused the boat crew of negligence, saying it took too long to launch a search. OzSail, the company that charters Pacific Star, shot back, placing the blame squarely on Ally and Rich.
Matt Lauer: They go through a long laundry list in their press release. They say "Allyson and Richard did not remain on the dive site." They say "Allyson and Richard did not follow the clear instructions of the dive instructor."
Ally Dalton: That's absolutely false.
Rich Neely: Absolute rubbish.
Ally Dalton: It's unbelievable that they would have the audacity to say that.
Rich Neely: I followed the instructions of the tour leader and was expected to be picked up, as promised, by the deckhand. And we stuck within the time limits.
Ally Dalton: It was their responsibility to make sure that they were looking out for us, and they retrieved us. Even, let's just say, hypothetically, we had strayed out of the dive site. It doesn't matter. You still retrieve your divers. You don't leave them and forget them and have them drift at sea for 19 hours.
OzSail declined Dateline's request for an interview, but in its press release, says that contrary to what Ally and Rich say, the dive instructor "physically pointed to the perimeter of the lagoon" and told them "not to leave" it. Other divers on the boat told us the briefings they received made that very clear.
OzSail goes on to say the Pacific Star instigated a "full and proper search" -- and, "Emergency services were alerted within 1 hour."
Meanwhile, as rumors swirl about million-dollar payouts for the story, headlines have floated another possibility: Was it all staged?
Matt Lauer: This suggestion, Rich and Ally, that this is a hoax.
Ally and Rich Neely: Yeah.
Matt Lauer: That you two, maybe you, after seeing "Open Water" the movie decided "Let's go live it. Let's go recreate the scenario, but let's take some precautions along the way as to not really put our lives in danger." For example there are people who said you went out there with a water bottle, which is unusual for a dive like this. Did you take water out there with you?
Rich Neely: No.
Ally: Absolutely not.
Rich Neely: I've never taken a bottle of water on a dive in my life.
Matt Lauer: And also they talk about the thickness of these wetsuits. You had a 7 millimeter dive suit on, you had a 5 millimeter suit on. They say that shows that they were preparing for a long ordeal in the water.
Rich Neely: Mmm. Yeah.
Ally Dalton: We always dive with these wetsuits. and we dive with these wetsuits in 81 degree water in Thailand.
There were even reports that the couple was toting a sophisticated shark-repellant device. But at a party to thank their rescuers, Ally and Rich angrily denounced all the rumors, denying that they were diving for gold, and stressing they have not made millions from TV interviews or movie deals.
Ally Dalton: To even insinuate that we would ever plan something like this is beyond us.
Rich Neely: We don't have a story. We have the truth. We have not told any lies and we don't have to remember any lies.
The persistent doubts have tested a romance that isn't yet a year old, though Ally and Rich are finding refuge in the deep love kindled by their ordeal.
Matt Lauer: You must have learned a lot about Rich during those 19 hours?
Ally Dalton: Oh wow. I already thought he was amazing before, but his strength and his determination and his presence of mind to do things like dropping the tanks and the weight belts and tying us together. Phenomenal.
Matt Lauer: What you'd learn about Ally?
Rich Neely: That she's very sensitive. That when she needs help, she realizes it and accepts it. And that when I need help, even when she's at the lowest point probably of her life, she's there for me.
Matt Lauer: Keep holding hands.
Ally Dalton: Yeah. We haven't let go very much.
Ally Dalton has been diagnosed with acute stress disorder following her ordeal at sea. She and Rich Neeley have spoken to lawyers and are considering a lawsuit against the dive company.