While performing in the musical Beauty and the Beast, he was suffering headaches because he was dehydrated, the actor tells Playboy in its December issue. Is solution: Drink a lot of water. "I'd just gone to the bathroom, but waiting in the wings, I was like, 'Bloody hell, I need to go again.' I thought, 'I'll be all right,' " he says.
But it wasn't all right: While getting ready to sing the last note of his big duet, the star says, "I thought ... 'if I sing this note, I'm going to pee my pants; if I don't, I'm going to be humiliated.' The actor in me took over. I was singing, thinking, 'Wow, I'm peeing my pants.'
Audience Laughed"When I finished, I immediately turned upstage, looked down and couldn't see anything. I thought, these red tights must be waterproof. I was laughing as if I had gotten away with it. But the audience was looking at me funny. It had seeped through, and my pants were completely wet. The audience could see it."
The Aussie hunk, 40, says he's had fans lose control too, but laughs it off. "Once during The Boy From Oz a woman ran down to the front of the stage while I was doing the show," he tells the magazine. "She said, 'Hugh, I've always wanted to do this,' and lifted her top. She had these massive tits. I just pissed myself laughing and said, 'I'm glad you got that off your chest.' "
The Aussie star (Australia opens Nov. 26) says growing up Down Under, and getting his acting chops there, has made him stronger – a quality he says many Australian actors share.
He praises Heath Ledger in particular. "He was totally driven by the creative spirit," says Jackman, "a character actor who happened to be unbelievably good-looking and have some leading-man qualities."
Who's your Favorite Star Under 35? PEOPLE.com and the People's Choice Awards are counting your votes! Click here to vote now!
See Hugh's 'sexiest' moment