A Teen Wolf Star’s Girlfriend Cheated on Him… According to the Other Man!!

Chad Michael Murray

While filming House of Wax, Chad must have conveniently forgotten the fact that he was married to his One Tree Hill co-star, because he wasted no time hooking up with his HoW co-star, Paris Hilton. This led to the divorce between Sophia and Chad that broke hearts 'round the world.

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Kristen Stewart

KStew was nearly burned at the stake by the public after photos of her hooking up with her Snow White and the Huntsman director, Rupert Sanders, were released. (Okay, so he wasn't her co-star, but close enough!) This was such a big deal because she had still been in a super-high profile relationship with Robert Pattinson, at the time, which has since ended.

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Kaley Cuoco

After Kaley and her husband of 21 months called it quits, lots of speculation suggested that it was due to her having an affair with her Big Bang Theory co-star, Johnny Galecki. The two have since tried to hush those rumors, but it IS a little, fishy, considering that, in addition to being her costar, Johnny also happens to be her ex-boyfriend.

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Brad Pitt

Honestly, if you were alive in the early-aughts and you didn't form a strong opinion on whether you were on on Team Angie or Team Jen, then were you really even living? Because after the news leaked that Brad had reportedly cheated on his then-wife Jennifer Aniston with his now-wife Angelina Jolie, everyone and their mother had a(n oddly strong) opinion on the matter.

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Ryan Phillippe

Ryan and Abbie Cornish broke up early last year, after having met on the set of the 2008 movie Stop Loss. Their meeting and subsequent romance was at the heart of Ryan's divorce from Reese Witherspoon, with whom he has two kids, since they were already together when Ryan began seeing Abbie.

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Claire Danes

Claire cheated on Billy Crudup with Hugh Dancy, after they met on the set of the movie Evening. She ended up leaving Billy for now-husband Hugh, but the real twist of the knife for Crudup had to have been the fact that he left his own wife, Mary Louise Parker, for Claire in the exact same way just two years earlier!

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Josh Hartnett

Josh was famously a Hollywood playboy during the height of his fame, and that included during his two-year relationship with Scarlett Johansson, when he was seen hooking up with a ~mystery lady~ on the set of one of his films.

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Johnny Depp

Johnny and Amber Heard may be a married couple these days, but back in 2009, Johnny was still with his longtime partner and the mother of his children, Vanessa Paradis. However, soon after filming began, rumors began swirling that Johnny had began an affair with Amber; the fact that they're now together sort of makes it seem like there was some truth to those rumors.

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Marilyn Manson

While making the movie Phantasmagoria: The Visions of Lewis Carroll, Marilyn, who was in a relationship with Dita Von Teese, met and began a relationship with Evan Rachel Wood. Marilyn and Evan actually ended up getting engaged, as a result, but the union was soon called off.

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Billy Bob Thornton

Angelina Jolie is no stranger to wedging herself between already-existing couples, as she was also the downfall of Billy Bob and Laura Dern's relationship. Well, to be fair, it was also Billy Bob who couldn't keep it in his pants on the set of Pushing Tin.

Nor could he afterward, when he full on married her, despite the fact that he was still in a relationship — and living — with poor Laura, who had just left town to go film a movie of her own, sans cheating.

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LeAnn Rimes & Eddie Cibrian

LeAnn and Eddie are shameless about the double cheating scandal that they caused after hooking up while filming Northern Lights. The two openly admit to not having any regrets about breaking up two marriages —LeAnn's to Dean Sheremet and Eddie's to Brandi Glanville.

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Meg Ryan

In 2000, Meg was married to Dennis Quaid. However, that didn't stop her from romancing her Proof of Life costar, Russell Crowe, at the same time!

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