"Knight and Day" introduces us to an exciting new talent: Tom Cruise.
Sure, we know Tom Cruise after his three decades in the business. We know way too much about Tom Cruise, actually, thanks to his well-documented off-screen antics the past few years.
"Knight and Day" is a refreshing reminder, though, of why he is a superstar: He has that undeniable charisma about him and he really can act, something for which he doesn't always get the credit he deserves.
Here, he plays a Vintage Tom Cruise Role: He gets to be charming but also toy with the idea that he might be a little nuts. As secret agent Roy Miller, he has that twinkle in his eye and that sexy little smile but he's also strangely calm in the middle of elaborate car chases and shootouts — relaxed, articulate and abidingly courteous when most mortals would be freaking out. That's part of the fun of the character and the movie as a whole, that contradiction.

Cruise's presence also helps keep things light, breezy and watchable when the action — and the story itself — spin ridiculously out of control. That's the pervasive joke in James Mangold's film, based on a script by Patrick O'Neill (and an action picture is yet another random entry in the director's filmography, following "Girl, Interrupted," "Walk the Line" and the remake of "3:10 to Yuma"). "Knight and Day" is supposed to be a mission that's impossible, but gleefully so.
The film starts with Roy confidently landing a plane in a cornfield after killing the handful of people on board — people who were there to kill him anyway. (The casual approach to a staggering body count is also a clue we're not supposed to take any of this seriously.) The one person who survives is someone he now must protect: June Havens (Cameron Diaz), just a regular gal from Boston who was locked in the bathroom at the time and therefore clueless to the carnage.
Cruise and Diaz, who previously shared the screen in 2001's "Vanilla Sky," are oddly appealing together with their disparate personalities: He's self-assured, she's skittish, and the way "Knight and Day" is shot, you can't even tell that she'd tower over him in real life. A scene in which she's high on truth serum allows her trademark vibrancy to shine through. But the romance between them feels forced and is one of the movie's chief weaknesses. If they'd simply been attracted to each other and exchanged some flirty banter, just as much would have been at stake. Having June fall for Roy quickly, and having things wrap up neatly at the end the way they do, seem too cutesy and pat.
Before that, though, the two hop all over the globe trying to protect some super-duper battery and its nerdy creator (Paul Dano) from another agent (Peter Sarsgaard) who may be the true bad guy; but then again, Roy may be the one who's gone rogue. Although who are we kidding here? Cruise is the star and the ever-versatile character actor Sarsgaard plays his adversary. It's obvious which is which. (Sarsgaard doesn't get enough to do; neither does Viola Davis, criminally underused as his boss.)
The running gag is that Roy drugs June when something ugly is going to happen that she either shouldn't see or wouldn't be able to handle. Then poof! She wakes up in another country wearing different clothes. If you stopped to think about it, this tactic would seem more than a little creepy; it's downright invasive. "Knight and Day" plays this motif for laughs, but the added benefit is that it keeps the action moving fluidly.
And as is the case with much of the movie, this is one element you probably shouldn't stop to think about too hard.
Don't think too hard about the title, either. The meaning becomes clear as June learns more about Roy.
"Knight and Day," a 20th Century Fox release, is rated PG-13 for sequences of action violence throughout, and brief strong language. Running time: 109 minutes. Two and a half stars out of four.