Julian Assange probably can’t slip out of the Ecuadorian embassy to enjoy London’s attractions, but at least there’s movie night.

Australian director Robert Connolly hopes to arrange a special screening at the embassy of his new film Underground for Assange, the WikiLeaks founder, currently holed up with the South Americans as they “assess” his application for political asylum, preventing Swedish authorities from extraditing him to face sex charges and Americans from getting one step closer to their prime quarry.

Connolly’s “unauthorised” biopic of the Townsville-born activist will screen on the Ten Network in Australia but had the rare distinction for a television movie of making its premiere on the big screen at the Toronto Film Festival. Connolly (The Bank, Romulus My Father, Balibo) said he has been “overwhelmed” with the reaction to the film and told the large appreciative audience after the screening he was “looking forward to showing him and seeing what he thinks. I hope he likes it”.

Underground focuses on Assange’s late teenage years and his role in Melbourne’s now much-vaunted, pre-worldwide web hacking scene. Using the hacking name Mendax, Assange managed to access elite US military and other security sites in cohorts with a loose Australian brethren in the late 1980s and early ’90s. His exploits attracted the attention of international security bodies and ultimately arrest in Melbourne along with at least two friends and confidantes.

Assange, a father as a teenager, had a transient and reportedly, at times, turbulent upbringing with his activist mother’s partner a member of a cult known as “The Family”.

“I made the decision early on to tell a story, without Julian’s approval — although he was very good about it — about this formative period, in the hope it’ll cast some light on why he has become the man he is,” Connolly told Crikey. “It’s also about a time in history when a new form of social activism takes shape, one that has evolved with the internet. I think this helps put a few things in perspective.”

Connolly’s source material for the film was the 1997 Suelette Dreyfus book Underground, which laid out the practices of the early hacking community in Australia. Assange was a researcher for the book and his hacker persona’s activities was a focus of its narrative. “I read it in a weekend and knew I had to make a film,” Connolly said.

The director was joined on stage after the screening for a Q&A with several of the film’s stars, including US-based Australian actor Anthony LaPaglia and newcomer Alex Williams, who portrays Assange. Golden Globe winner LaPaglia, best known for his long-running stint on US broadcast drama Without a Trace, reiterated his recent criticisms of the Australian government over its lack of support for Assange during the Q&A.

“As an Australian citizen he deserves the presumption of innocence until proven guilty of whatever charge they come up with [however] the government has gone on the record saying they’ll hand him over,” he said. “What basically ground [the war in] Vietnam to a halt was the media coverage, night after night, but that doesn’t happen any more because you have embedded journalists. The military bring the journalists to where they want them to be. So you don’t get the full picture.

“We need transparency and that’s why you need guys like Julian Assange,” he said to generous applause.

Connolly and LaPaglia expressed the hope the film could help inform Australian and international opinion about Assange, who has been maligned for his pivotal role in accessing and releasing via WikiLeaks thousands of US diplomatic secrets. “We’re seeing greater interest in what he was seeking to do,” Connolly said. “At first a lot of people were just overwhelmed by it all.”

Connolly admitted to being nervous about the Toronto screening while LaPaglia  said he was “shocked” by the film. “It was really good,” he said after seeing it in its entirety for the first time.

Made on a “TV budget”, Underground seems to occasionally lurch towards small-screen melodrama in packaging the young Assange’s story, but Connolly’s deft touch in mixing the personal and political — and fine performances from LaPaglia, Rachel Griffiths as the activist’s mother Christine, and Williams as the young “genius hacker” — had the Toronto audience hooked.

Spotlighting the clunky technology of more than 20 years ago is amusing, but Connolly hopes the focus remains on the circumstances he believes propelled Assange to construct the complicated global path he hacked for himself.

“I wanted to make a film young people will watch, not just those who remember ‘those’ times,” Connolly told Crikey. “There were a lot of difficult decisions about how much we had to explain things to an audience who think the internet is like running water, just turn it on.”

Underground is one of six Australian films featuring at the Toronto Film Festival, now widely considered to be the world’s second biggest celluloid fest behind Cannes.