ET is with 'The Ugly Truth' star Eric Winter in the green room as he prepares for his appearance on "Jimmy Kimmel Live!" The star opens up about working with co-star Katherine Heigl, filming some revealing scenes, and a practical joke he played on set!

Eric tells ET's Thea Andrews that he is very excited about being on the talk show, and that it is his first appearance on a late show.

"This is my first, ugh, virgin experience of late night I guess," he says. "I don't usually get too nervous with these things. I'm more excited than anything else. I think Kimmel's great."

In the 'The Ugly Truth,' the 33-year-old actor plays the object of desire for Katherine Heigl's character, and the actor tells ET what it was like meeting and working with his co-star.

"She was a fan of 'Brothers & Sisters,' so she, from the moment I was in the running, she had signed off on me," he says. "She was just like, 'Oh my God, I'm a fan of you on the show 'Brothers & Sisters.' It just broke down the ice really easy. She's been so successful with everything she's done. With the movie career, with 'Grey's'. It was a refreshing to see that. It was a very comfortable set for me."

Eric also tells ET about a practical joke he played on set while filming a revealing scene, and about staying in shape for certain scenes in the film -- watch the video for more!