O'Donnell said it was like getting paid to go an adventure camp.
"The training was not that bad. It wasn't like they were drill sergeants out there. But there was so much technically to pick up. I didn't know how to put a harness on, the proper knots to tie. It was really important we got familiar with that. So much of climbing is being comfortable with the equipment. A lot of times we'd be shooting where we're hanging off these cliffs. If you don't feel comfort and trust your equipment, you won't be able to get into your character," explained O'Donnell.
They filmed on a mountain in New Zealand.
"The whole idea of getting up every morning and getting in a helicopter and landing on some little mountain peak we had a really small crew. We were roped together and climbing down and setting up the camera. It was wild," said O'Donnell.
In the movie he plays a mountain climber trying to rescue his sister at 24,000 feet.
"We had some of the best climbers in the world training us. And then they were also there as our advisers on the set. We're filming at 10,000 feet. It's nothing compared to the so-called death zone at 24,000 feet," he said. The climbing experts kept reminding the actors that at such a high altitude their breathing would always be labored.
In one scene, it looks like O'Donnell makes a huge leap across an abyss.
"Obviously, that is done with stunt guys," said O'Donnell. "Part of it is me, part of it is stunt guys, part of it is blue screen. Pretty amazing how it's put together," he said.
Another scene shot with him hanging off a helicopter was also party computerized.
"Most of that was done in the stage, believe it or not," said O'Connell. "I've never been so banged up in my life. We were just getting tossed around the whole time."
He said that the scene was shot using "the world's largest mechanical bull. It was just rocking around and then they had it on top of a crane. There was a ledge there we were being thrown off onto. It's movie magic."
O'Donnell is definitely not doing too many of his own stunts because he has two babies at home now.
"When I got cast in this film, I didn't have any kids and now I've got two. A 15-month-old and a 1-month-old. It's unbelievable. It just completely challenges your life, definitely for the better," he said, although he added, "You don't get as much sleep. And traveling around, doing all the press for this movie, it makes you sick to be away from them."
O'Donnell grew up in Chicago and has six older siblings. He did modelling as a child and at 17 was cast as Jessica Lange's eldest son in Men Don't Leave. His breakthrugh role was in Scent Of A Woman playing opposite Al Pacino. He graduated from Boston College with a B.A. in marketing.
In 1997 O'Donnell married his long-time girlfriend Caroline Fentress, a kindgergarten teacher.
Vertical Limit, 2000
The Bachelor, 1999
Cookie's Fortune, 1999
Batman & Robin, 1997
The Chamber, 1996
In Love and War, 1996
Circle of Friends, 1995
Mad Love, 1995
Batman Forever, 1995
Blue Sky, 1994
The Three Musketeers, 1993
School Ties, 1992
Scene of a Woman, 1992
Fried Green Tomatoes, 1991
Men Don't Leave, 1990
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