Daniel Radcliffe named his 'Escape From Pretoria' wig after Bradley Cooper.
The 30-year-old actor donned the hairpiece to portray anti-apartheid activist Tim Jenkin, who escaped from prison in 1979, in the new movie and although he was initially "against" it, he quickly realised he wouldn't be able to transform his own locks to be like the styles of the era.
He said: "Initially, I was against the wig. But even if I grew my hair out, it wouldn't grow like a dude's in the 70s.
"So we tried one out and I was like, 'Is this me or does this fit really well?'
"We named it Jackson after Bradley Cooper's character in 'A Star is Born.' "
For Daniel, the hardest part of making the movie was adopting a South African accent.
He told Empire magazine: "The hardest part was that I was doing a South African accent but we were making the film in Australia, so you can find yourself being dragged from one accent to another.
"I would definitely say it was not an easy accent, but Tim was more Anglo-African than Dutch-African, which was slightly more merciful."
And the British star also had to spend a lot of time preparing for one particular scene.
He explained: "The main thing I physically prepared for was a scene where I try to unlock the outside of my cell from the inside.
"So whenever other people were shooting, I'd go into my cell with my stick and mirror and just keep trying to catch the key once it left the lock.
"You could feel the crew wanting to cheer when I actually did it, because everyone had been watching this f***ing key dance around this lock for ages."
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