It makes sense that so many stars fall in love on movie sets - when you're cast in a project because you have natural chemistry with someone and then you have to pretend to be in love with them, it's easy for that spark to ignite.
Whether that love will last after filming is another story, but here are 20 examples of two co-stars who were so clearly madly in love with each other as they shared the screen, they took their romance offscreen as well. Hey, there's no fighting chemistry.