ET was with Bradley Cooper and Justin Bartha at screening of their new comedy, 'The Hangover,' in New York on Thursday night. The two funnyman told us how they think their flick will fare at the box office this weekend against Will Ferrell's 'Land of the Lost,' and they opened up about the death of David Carradine.

"I'm looking forward to seeing ['Land of the Lost']," said Justin, "and I've seen this movie ['The Hangover'] three times, and I can't wait to see it again."

"I hope they both do well," Bradley added of the films, which open in theaters today.

In 'The Hangover,' Doug (Bartha), the groom-to-be, heads to Vegas with best buds Phil and Stu (Cooper and Ed Helms) and future brother-in-law (Zach Galfianakis) for his bachelor party. After a long night of partying, they wake up with some unanswered questions -- and some major problems.

Click the video for more with Justin and Bradley, including their reactions to David Carradine's death. Plus, other stars at the screening, including Christopher Meloni and Jill Hennessy, also reflect on the loss. For more movie news and exclusives, head over to ETonline's Summer Movie Guide!