Michael Caine rehearses every line of his scripts 1,000 times.
Sir Michael Caine
Caine - who has appeared in over 115 films and been nominated for an Oscar six times - likes to ensure he's word perfect before stepping on to set so finds the time to practice wherever he can.
He said: "I rehearse on my own and by the time I have come on to a set I have said the line to myself a minimum of 1,000 times.
"I've never used a mirror - I just do it anywhere. I just sit there talking."
The 'Kingsman: The Secret Service' actor never enlists the help of other people when it comes to learning his scripts as he'd rather his co-stars' lines come as a surprise during filming.
He explained on '60 Minutes: "Because it's conversation, so when the other actor says the line I've never heard it. That's the trick.
"I don't want to be in the situation where I know what he's going to say.
"I know what my bloody answer is. I've said it a thousand times. So I listen to what he says and that's what makes the difference.
"That and having the confidence of knowing you're not going to forget the line."
But Michael admits he takes "twice as long" to learn his scripts now than it used to.
He added: "You know what happens when you get older; in my case I don't forget the lines but it takes me twice as long to learn the bloody things. It takes forever."
Despite the efforts the 'Alfie' star puts in outside of work, his wife Shakira is understanding.
She said: "He rehearses and rehearses. He studies his lines everywhere.
"If it's a movie where he's working for two weeks or two months he puts in the same effort into it. But he goes over and over his lines.
"We could be walking on the beach in Miami, we could be on a boat in the South of France, we could be walking in our garden, he could be feeding the ducks in our pond, he could be with our grandchildren. He goes over and over his lines and that has become a way of life with him.
"I'm accustomed to this but I realise and he does too that excellence is only by hard work."
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