The director of Alan Turing biopic The Imitation Game has described the film as "a tribute to being different".
Norwegian Morten Tyldum said he became obsessed with the British code breaker - a pioneer of modern computing - after reading the script.
“I was completely blown away. Why wasn’t he on the cover of every history book?” he said, at the Toronto Film Festival.
Turing - portrayed by Benedict Cumberbatch - is credited with decoding the Enigma machine and decrypting German naval messages, in effect changing the course of World War Two.
But his later life was overshadowed following a conviction in 1952 for gross indecency, at a time when homosexuality was illegal in Britain.
He was chemically castrated and committed suicide in 1954.
Tyldum said the film had "many layers", insisting it was not just your average thriller: "It’s a human rights [movie], a gay rights movie," he said.
"It’s a blessing to find a project you feel you have to make or you’ll die," he told reporters at a press conference.
Cumberbatch added: “If we do anything right with this film, it is to bring Alan to a broader audience.
"There’s a lot of his story that comes as a real shock to people.
"There was something subtle, uncompromising and unusual [about him], but also very quiet and stoic," he explained.
"He didn’t knowingly martyr himself. He didn’t see himself as a victim or a hero, he just did his work and behaved true to his nature."
The Imitation Game was shown at the festival a couple of days after The Theory of Everything, a biopic about physicist Stephen Hawking, starring another Briton, Eddie Redmayne.
Both Cumberbatch and Redmayne have been praised for their respective performances, with the suggestion of probable Oscar nominations.
But the Sherlock star dismissed the notion that the two films are competitors.
"I don’t like thinking of films being in competition with each other," he said.
"It’s absurd. As long as they’re both able to find an audience, it’s not a problem."
The actor admitted he had not seen Redmayne’s film yet, but had high praise for the star.
“He’s a phenomenal actor – he’s been a friend, but also a talent I’ve admired for a long time.
“I’ve always thought he was brilliant and the rest of the world is catching up. I hear it’s just stunning, I can’t wait [to see it].”
The Imitation Game will open at the London Film Festival next month and will be released in UK cinemas on 14 November .