Eddie Redmayne made a "complete fool" of himself in front of Stephen Hawking.
The 'Theory of Everything' actor met the physics professor - who he portrays in the award-winning biopic - briefly before filming began and admits his nerves got the better of him.
He said: "I only got to meet him about five days before we started filming. I'd done all this research and I suddenly got the opportunity to meet him. I was like, 'What if I've got it wrong?'
"It takes him maybe like eight minutes, or six, seven, eight minutes to write a sentence and so it's a very unique rhythm.
"There are these long, long pauses and I was nervous and I have a hatred of silence anyway and so I just, I basically just made a complete fool of myself and arrived and just started spewing forth information about Stephen Hawking to Stephen Hawking for 45 minutes and it was genuinely pretty tragic.
"Eventually I calmed down and he was just looking at me going, 'Really? You're going to tell me about myself? I do know all this, I do live it'. And then eventually I calmed down and then he said a few specific things."
Despite the embarrassing encounter, Eddie was left very impressed by "powerful" Stephen and his sharp sense of humour.
He added to the new issue of Loaded magazine: "But really what I took away was the strength of his charisma and this sort of incisive wit.
"It's like this mischief, this glint that he has in his eye.
"He's very powerful even though it's difficult for him to communicate. He absolutely runs a room."
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