Hugh Jackman's 'Wolverine' preparations make him "angry".
The 46-year-old actor undergoes a dramatic transformation when he has to bulk up to play the mutant and gets increasingly "annoyed" by the weight-gain diet plan and regular exercise regime he has to follow.
He said: "Wolverine is very determined and visceral. It's not just his anger that drives him, although he obviously uses anger to his advantage.
"I don't get angry while playing him. I get more annoyed in the months leading up to the start of filming and having to go on this insane diet and training regime in order to put on 25lbs and bulk up.
"You'd be angry too if you were eating 6,000 calories a day and bench-pressing 350lbs."
While being Wolverine makes him angry, Hugh insists he never loses his temper with wife Deborra-Lee Furness or their kids Oscar, 14, and nine-year-old Ava, though that can be a challenge of his acting skills.
He told Psychologies magazine: "I lose my temper very rarely and, when I do, I feel really miserable afterwards. But never with Deb and never with my kids.
"Although when they misbehave, you learn to control your emotions and exercise as much self-control and reason as you possibly can.
"It's better to tell your kids that they are driving you crazy and being impossible than to yell at them."