David Thewlis says he cried over The Lady script
David Thewlis says he cried when he first read the script for his new film, The Lady.
The actor dropped out of one of his existing projects so he could take part in the film.
He said: "It was one of the quickest decisions I've ever made. I was actually signed to do something else and I pulled out within eight hours of reading [The Lady].
"It made me cry actually, which I've never done at a script before."
The Lady is based on the life of Aung San Suu Kyi, a Burmese politician who spent 15 years under house arrest.
She is known as a pro-democracy leader and won the Nobel Peace Prize in 1991.
The actor describes Suu Kyi as an "extraordinary living icon".
"I think a lot of people maybe don't know about her because her name is difficult to say. We should all know about this woman, she's as inspiring as Ghandi, Mandela and Luther King," he said.
Thewlis portrays Suu Kyi's husband, Michael Aris, in the film.
The actor has previously starred in The Omen, The Boy In The Striped Pyjamas and five of the Harry Potter films.
Filmed in secret
Given the controversial subject of the movie, Thewlis says they tried to keep the filming low-key.
"The most amazing thing about the making of the film is we shot it covertly. We shot entirely in secrecy," he said.
"We shot it in Bangkok, keeping it from the Burmese authorities. We had to enter the country under false pretences saying we were making a different film."
The 48-year-old says he was surprised that they managed to keep the shooting of the film secret for so long.
"What I found incredible was right from the first day we started until the day we left Bangkok, considering we're in this day of Twitter and Facebook, if you had Googled Aung San Suu Kyi along with my name or Michelle Yeoh's name, you would not have found one Google hit.
"It's extraordinary that we managed to film it under such secrecy."
The actor told Newsbeat the cast were shocked when Suu Kyi was released in November 2010.
"Halfway through making the film she was released, which was an astonishing night for all of us in the cast," he said.
"We were with her son who hadn't spoken to her for 10 years. The phone went in our hotel room and it was her, and we all managed to have a chat with her on the night she was released."
Thewlis has yet to meet Aung San Suu Kyi in person, but his co-star Michelle Yeoh spent time with her in Burma while shooting the film.
Yeoh was later barred from entering Burma when she tried to visit Suu Kyi a second time.
Thewlis said: "I'm not sure what my chances are of getting to meet Suu Kyi and getting inside Burma in the current climate."
The Lady is released in the UK on 30 December.