As President Obama and Congress begin to debate gun control in Washington, one movie at Sundance -- "Blue Caprice" -- has already weighed in on the tragedy of mass shootings: killers aren’t born, they’re made.

Alexandre Moors' film tells the story of the Beltway snipers, two unknown criminals who killed innocent civilians at random in the Washington D.C. area in 2002. Rather than focus on the senseless killings, scribe R.F.I. Porto and Moors convey how the two assassins came to commit those crimes, how an embittered John Allen Muhammad (Isaiah Washington) took 17-year-old Lee Boyd Malvo (Tequan Richmond) under his wing and turned him into a ruthless assassin.

Though Beltway killings happened 10 years ago, the audience and filmmakers at Saturday’s premiere found them more pertinent than ever in the wake of recent mass shootings, such as the one in December at Sandy Hook Elementary School.

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When an audience member asked whether the movie made the killers seem sympathetic, April Yvette Thompson, who has a brief part as Malvo’s mother, jumped in.

“Young people going on killing sprees happens a lot; it recently happened,” the actress said to much applause. “All the focus is on the people killing, but killers aren’t born they’re made. We have to question how society starts treating killers.”

Malvo’s turn from a sweet but lost teen into one of America’s Most Wanted makes for a tough watch, and the crowd repeatedly gasped or recoiled in response to gunshots and other violence on screen.  

While Thompson was vocal, several cast members, seeing the film for the first time, were left grasping for words.

“This film is not the movie I thought I made,” Washington (left with Richmond) said. “I thought I was making ‘The Bourne Identity.’ [Alexandre] kept telling me we’re not making that movie, and he was right.”

“Wow. So much for Matt Damon,” he added. “That wore me out.”

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Washington’s character is primarily responsible for the descent into darkness, for transforming his adopted son into a killer, and their car, which provided the film’s title, into a vehicle of destruction.

Muhammad meets Malvo in Antigua and brings him to America, offering him shelter and the father figure he has never had. Though Muhammad starts off warm, he earns Malvo’s love and loyalty through brutality.

Malvo first calls Muhammad his father when the former army officer binds his hands and feet and leaves him tied to a tree -- an attempt to prepare Malvo for the cruel world, to sap him of any remorse.

As they fight in the woods, beating on one another, their mutual rage brings them closer together. As Muhammad practices with a massive rifle to clear his head, Malvo reads aloud a book about being a sniper.

Finally, when Muhammad says shoot, Malvo murders.

Still processing those scenes, Washington reflected on his own childhood in a single-parent home, searching for a solution to the inexplicable violence.

“What I walk way with is it has to start somewhere, with the leadership in our homes,” he said. “Where are our leaders? Where are our fathers?”

To prepare for the movie, the director and some of his actors went shooting. While Moors described it as “terrorizing,” Washington declined to comment.

And then there’s the weapon used in the film.

“The gun is a Bushmaster 223,” Porto said. “It’s been used in five of last six mass American shootings.”