If what "I Know What You Did Last Summer” star Freddie Prinze Jr. says is true, Kiefer Sutherland is one of the most unprofessional actors in Hollywood. The late '90s heartthrob said Sutherland was a nightmare to be on set with when the two worked together on the hit Fox show “24,” but Sutherland denied that there was a feud between the two.

Both Sutherland’s representative and a Fox official told TMZ  the two actors worked together more than five years ago , with the Fox source saying it was “strange” that Prinze would make the comments now. Sutherland was "nothing but professional during the run of the show and is beloved by cast and crew,” according to the source.

Sutherland’s rep responded with the following official statement to TMZ: "Kiefer worked with Freddie Prinze Jr. more than 5 years ago, and this is the first he has heard of Freddie's grievances."  The rep added, "Kiefer enjoyed working with Freddie and wishes him the best."

Previously, Prinze told ABC News he almost quit “24” because of the Fox star. "I hated every moment of it,” he said about his stint on the hit show in 2010. “It was terrible.”

"Kiefer was the most unprofessional dude in the world," Prinze, 38, said. "That's not me talking trash, I'd say it to his face. I think everyone that's worked with him has said that."

He claimed the experience was so horrible he contemplated quitting acting and took jabs at Sutherland’s height. "I went and worked for Vince McMahon at the WWE for Christ's sake and it was a crazier job than working with Kiefer," he said. "But, at least he was cool and tall. I didn't have to take my shoes off to do scenes with him, which they made me do. Just put the guy on an apple box or don't hire me next time. You know I'm 6 feet and he's 5'4."

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