Vince Vaughn & Reese Witherspoon
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Vaughn and Witherspoon reportedly clashed on the set of Four Christmases, which isn't surprising, considering Vaughn's tendency to improvise and Witherspoon's stick-to-the-script attitude.
Leonardo DiCaprio & Claire Danes
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While both actors were fairly young when cast in 1996's Romeo & Juliet, Danes found 22-year-old DiCaprio immature and impossible to work with. She maintained that disdain for 15 years, turning down a role to play Helen Gandy alongside DiCaprio's J. Edgar Hoover in 2011's J. Edgar.
Anthony Hopkins & Shirley MacLaine
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Hopkins took no pleasure in sharing the big screen with costar MacLaine. After working together on A Change of Seasons, Hopkins called her "the most obnoxious actress" he'd ever worked with.
Patrick Swayze & Jennifer Grey
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Swayze and Grey may have appeared to have chemistry in Dirty Dancing, but Swayze found Grey silly and immature. "She'd slip into silly moods, forcing us to do scenes over and over," he wrote in his memoirs. "She seemed particularly emotional, sometimes bursting into tears if someone criticized her."
Tony Curtis & Marilyn Monroe
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While Monroe and Curtis started filming Some Like It Hot as lovers, they certainly didn't end that way. Curtis said Monroe had gone funny and that kissing her "was like kissing Hitler." Monroe's Prince and the Showgirl costar Laurence Olivier also found her unpredictable and unprofessional.
William Baldwin & Sharon Stone
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If you've seen the 1993 film Sliver, it comes as no surprise that Baldwin and Stone despised each other during filming; the couple had absolutely no chemistry on-screen. While filming one kissing scene, Stone bit Baldwin's tongue so hard he supposedly couldn't speak for a week.
Nick Nolte & Julia Roberts
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Nolte and Roberts don't mince words when it comes to talking about their relationship. After wrapping on I Love Trouble, their feuding was so bad that even Roberts admitted, "It's no secret that Nick and I didn't get along like a house on fire."
Pierce Brosnan & Teri Hatcher
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During filming for Tomorrow Never Dies, Brosnan was constantly complaining about Hatcher's tardiness. It was later revealed that she was experiencing morning sickness, and Brosnan rescinded his comments: "I got very upset with her," he told Italian Vanity Fair. "She was always keeping me waiting for hours. I must admit I let slip a few words which weren't very nice."
Ryan Gosling & Rachel McAdams
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The Notebook is arguably the most famous love story of our generation, but, according to director Nick Cassavetes, its leading actor and actress despised each other. Gosling even tried to have McAdams replaced! The couple must have gotten over it, however, because they dated for a time after the movie was completed.
Kenny Baker & Anthony Daniels
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While R2-D2 and C-3PO weren't a romantically involved couple, the Star Wars duo is still one of the most iconic in history. So, it comes as a shock that actors Baker and Daniels couldn't stand each other!
Richard Gere & Debra Winger
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Gere and Winger may have played lovers, but the two avoided each other as much as possible on the set. Winger said talking to Gere was like talking to "a brick wall."
Dustin Hoffman & Meryl Streep
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How anyone could dislike Meryl Streep is beyond us. But Hoffman was reportedly annoyed that Streep had proposed a number of rewrites to the Kramer vs. Kramer script, and he tried to veto each one. Looks like the changes paid off, though, because Streep won her first Academy Award that year for best supporting actress.
William Shatner & George Takei
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Chad Michael Murray & Sophia Bush
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Murray and Bush met on the set of "One Tree Hill" and eventually married, but their relationship turned sour after Murray allegedly cheated on Bush with his House of Wax costar Paris Hilton. The couple had to work together for four more years after their divorce in 2006.
Robert Downey, Jr. & Terrence Howard
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You may have noticed that Iron Man's close friend Rhodey looked a lot different between the first and second Iron Man films. That's because Terrence Howard was replaced with Don Cheadle after Howard claimed that Downey "pushed him out" of the franchise and stole his money.
Jamie Dornan & Dakota Johnson
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The 50 Shades of Grey costars were supposed to be the couple of the year, but they had such a profound lack of chemistry on-screen that the media began to think they hate each other. While this has never been confirmed, the two certainly aren't denying it. Awkward!
Kiefer Sutherland & Freddie Prinze, Jr.
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The unlikely duo costarred in Sutherland's smash hit TV series "24," but that doesn't mean they had to like each other. "I did '24'; it was terrible. I hated every moment of it," Prinze said. "Kiefer was the most unprofessional dude in the world. That's not me talking trash—I'd say it to his face. I think everyone that's worked with him has said that."
Shannen Doherty & Jason Lee
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While Lee played Doherty's love interest in the 1994 movie Mallrats, he did not get along with her off camera, and he wasn't the first. Doherty has a history of causing problems with costars, including both Jason Priestley and Jennie Garth from "90210" and Alyssa Milano on "Charmed."
Bette Davis & Joan Crawford
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The feud between Davis and Crawford has been called "the most notorious cat fight in Hollywood history." And for good reason. The actresses never had a nice thing to say about the other, especially after costarring together. "The best time I ever had with Joan," Davis said, "was when I pushed her down some stairs in Whatever Happened to Baby Jane."
David Duchovny & Gillian Anderson
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After nearly a decade of working together on "The X-Files," it appears that Duchovny and Anderson didn't always see eye to eye. "We used to argue about nothing," Duchovny said. "We couldn't stand the sight of each other." Hopefully things are better now: "The X-Files" reboot premieres in 2016.
James Franco & Anne Hathaway
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Franco and Hathaway have never starred in a movie together, and they probably never will, thanks to their disastrous job co-hosting the Oscars. After finishing the job, the duo loathed each other and didn't speak for years after.