Allison, 26, has dreamed of playing Peter Pan since she was a little girl, and she gushed about her first time flying in the harness.
"It's just an unbelievable feeling," she said. "It's a total rush."
But Allison admits that you can have too much of a good thing.
"You get addicted to it, you get cocky and you stay in the harness for two long, and then you get saddle sore which is a very particular feeling," Allison said, explaining that it's a similar feeling to being on a saddle for too long. "I have bruises everywhere ... but here's the thing, when you're playing a boy it's allowed. You can get beat up and it's totally fine."
Another pro to all the flying around is the calories she burns.
"After all the flying workout, I'm telling you I'm eating donuts a lot and bagels and everything sinful and it's never enough to keep me fueled," Allison said.
Peter Pan Live!, airing Dec. 4, also stars Minnie Driver as an adult Wendy Darling and Christopher Walken as Hook.