Oscar Pistorius will go to trial Monday in South Africa, a little more than a year after he shot his model girlfriend Reeva Steenkamp to death.
People around the world will tune into the trial as the accused is a famed athlete, dubbed “Blade Runner,” as he was the first double-leg amputee to participate in the Olympic Games.
Meanwhile, Steenkamp was a South African model of growing fame who spoke out often against domestic abuse of women.
Here’s what you need to know as the prosecution opens the case against a once-groundbreaking athlete, who became a suspected murderer overnight.
What are the charges?
Pistorius is charged with premeditated murder for firing four fatal shots through a bathroom door at Steenkamp on Feb. 14, 2013.
"The deceased had locked herself into the toilet cubicle, situated adjacent to the main bedroom. The accused armed himself with his 9-mm pistol and through the locked door, fired four shots at the deceased," reads the indictment.
Pistorius is also charged with violating provisions of the South African firearms control act for having 38 rounds of unlicensed ammunition in his home.
What evidence will the prosecution present?
Prosecutors said they have enough evidence to prove Pistorius killed his girlfriend with “direct intention,” following a heated Valentine’s night argument between the two.
“The accused killed the deceased because of the argument,” reads a prosecution report obtained by South African broadcaster ENCA. "Some of the State witnesses heard a woman scream, followed by moments of silence, then heard gunshots," the indictment said.
The report specifically detailed that one witness recounted: "The screams were extinguished at the same time of the last shots."
"You know it's going to be pretty much hard for you to argue that you still didn't know that the person who was screaming was your girlfriend," prosecution spokesman, Nathi Mncube told NBC’s Dateline.
The number and direction of the shots fired also indicates Pistorius intended to kill the person behind the closed bathroom door, according to the prosecution.
The report notes Pistorius called his friends, but not the police, immediately after the shooting, and when a security guard contacted the Olympian after the incident, “he indicated that everything was fine.”
Lastly, the daytime clothes Steenkamp was wearing and two iPhones she had in the bathroom with her seem to dispel the defense’s claim that the model had simply gotten out of bed to use the bathroom unbeknownst to Pistorius.
What will the defense argue?
Although Pistorius admits that he killed Steenkamp, the crux of his not guilty plea is the claim that he was entirely unaware that the woman he said he was “deeply in love” with was behind the door he shot at.
In a bail hearing, the athlete claimed that he mistook his girlfriend for a dangerous intruder and felt vulnerable without his prosthetic legs on.
"I heard a noise in my bathroom ... I felt a sense of terror ... I believed that someone had entered my house. ... I grabbed my 9-mm pistol," Pistorius stated before being released on the equivalent of about $112,000 bail.
And experts believe that Pistorius' unique condition could work in his favor.
“You need to take into account that this is a person who has persistently said that he's felt the most vulnerable on his stumps and was living, essentially, in a state of fear, in a state of terror,” Karyn Maughan, a legal correspondent for ENCA told Dateline.
The prosecution did conclude that the “Blade Runner” was “most likely” not wearing his legs when he fired the four shots.
The defense will contest that Pistorius lived in fear because his condition left him with the feeling he was unable to defend himself — coupled with the fact that South Africa has a staggering high violent crime rate.
Who will decide the verdict?
The South African legal system does not have trials by jury, meaning trial judge Thokozile Masipa will hold the ultimate responsibility in deciding whether Pistorius is innocent or guilty — and Masipa is known for fighting to thwart domestic violence.
The opening arguments, prosecution witnesses, closing arguments, the verdict and possible sentencing will be televised, South African Judge Dunstan Mlambo ruled Tuesday. Pistorius’ testimony — if he chooses to take the stand — and other defense witnesses will not be broadcast.
Mlambo has said that publicly airing the trial will help quiet those skeptics who assume the case will be unfair because the South African legal system is “perceived as treating the rich and famous with kid gloves whilst being harsh on the poor and vulnerable."
What would the sentence be?
Prosecutors are seeking a life sentence for Pistorius, and if found guilty of premeditated murder, he will face at least 25 years in prison before he can be considered for parole.
If found guilty of culpable homicide — equivalent to manslaughter in the U.S. — Pistorius could be put away for 15 years.
Pistorius could also serve prison time and have to pay a fine if found guilty of illegally possessing ammunition, according to the South African firearms control act.
Or, the Blade Runner could walk out of court as a free man.