There’s the age-old cliche of co-stars falling in love while making a movie. But what happens when one (or both) of those co-stars is already married to someone else? It occurs more often than you’d think, and the results are rarely pretty. The heart wants what it wants, and sometimes it wants the completely unavailable actor it’s sharing the screen with.

When two actors spend months filming romantic scenes together, sometimes those feelings stick around long after the cameras stop rolling. Other times, the intense process of making a movie reveals cracks in a marriage already on the rocks. Here are 12 movies that are responsible for ending real-life celebrity marriages.

Gallery — Co-Stars Who Hated Each Other:

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