Long before Julian Assange was known as the founder of WikiLeaks, he was a teenage hacktivist known by the handle Mendax. The new film Underground looks to expose that side of Assange, even as the media attention around the founder continues to reach epic proportions.

Underground, which premieres Saturday at the Toronto International Film Festival and will air on Australia’s Network Ten later this year, is a study in how Assange became Assange. Based on Suelette Dreyfus’ 1997 book of same name, the film traces how a Melbourne teenager became a member of the hacker group International Subversives in the late 1980s and first appeared on the radar of authorities all over the world.

“There was this joke when we were working on the script that our story was like a origin story of a superhero in a way that the hero realizes that they have superpowers, but have yet to realize they can save the world with them,” director Robert Connolly, who also wrote the script, told Wired. “We were looking at the idea that here was a young man who was incredibly gifted. Where and why did he transition into a man who devoted his life to WikiLeaks?”

— director Robert Connolly ‘We were looking at the idea that here was a young man who was incredibly gifted. Where and why did he transition into a man who devoted his life to WikiLeaks?’

The film, which stars Without a Trace’s Anthony LaPaglia as a detective investigating Assange and newcomer Alex Williams as the man himself, is coming at just the right moment in time. The WikiLeaks founder is currently holed up in Ecuador’s embassy in London, trying to avoid extradition to Sweden, where he faces questioning over alleged sex crimes and fears he will be sent to the United States, where he could face charges over WikiLeaks’s publication of classified U.S. diplomatic cables.

His life as an international data-dumper has been chronicled in more than a few documentaries and TV specials. At least one more from Oscar-winning director Alex Gibney could be coming, and both Dreamworks and producers Barry Josephson and Michelle Krumm are hustling to adapt books about Assange.

Connolly’s is the first narrative drama about Assange to hit the big screen.

“I think there’s a lot of people talking and projects in development and a lot of books optioned, [but] it’s exciting to be the first dramatic exploration of the man,” Connolly said from Toronto.

The chance to take liberties with Assange’s story — Dreyfus consulted on the script, but the WikiLeaks founder was never involved — gave Connolly some freedom. But although he could hypothesize about what happened between the hacker and his International Subversives brethren, “the young Julian Assange did not steal anything when he was hacking,” Connolly said, “I can’t change that.”

Underground delves deep into the influences that would lead the young hacker to eventually found Wikileaks, and explores the life of a man chased by authorities even before he was out of his teens. One of those things is his relationship with his mother Christine Assange (played by Six Feet Under’s Rachel Griffiths), who saw his brilliance and bought him a Commodore 64 and, in the film, goes to great lengths to protect her son. The other was the time period in which he grew up and became politically aware — after the fall of the Berlin Wall, on the verge of the first Gulf War, and before anyone knew the term “dot-com.”

To play the teenage Assange, Connolly had to find an actor from a generation that doesn’t remember the time before the Web. Williams, who plays the young hacker, was born a year after the events in film. The Perth native was discovered by Connolly’s wife and casting director Jane Norris, who picked him from the recent graduates of the West Australian Academy of Performing Arts. Considering Williams’ similarities to Assange, it might seem that he was lucky to look the way he did when he did, according to Connolly, “[my wife] said, ‘He’s not lucky, we’re lucky to have found him.'”

Although the actor studied quite a bit of video of his fellow countryman Assange to nail his character, he didn’t go too far and kept in mind the Assange of today is probably not so much like his teenage counterpart. He did, however, have to learn what a Commodore 64 is and how to operate it.

“I had never seen one of those before in my life!” Williams told Wired. “Here’s me sitting on my iPhone and you go back and you see the evolution of it and where it all comes from and the people who were pioneers in creating hacking and programming and its such a cool culture.”

Williams is also in the position of being the first actor to portray the WikiLeaks founder – if you don’t count Bill Hader’s imitations of him on Saturday Night Live. Regardless of what happens with Assange’s extradition, he’s still a lightning-rod figure. Is Williams worried about being typecast as an online whistleblower forever? Not really.

“To me it’s just a great character, whether he’s in the press or not,” Williams said. “I’m not too worried about being labeled, or being hunted by the U.S.”

Underground premieres at the Toronto International Film Festival on Saturday.