Mr. & Mrs. Smith (2005)

The infamous movie that spurred Brad and Angelina's affair, Mr. and Mrs. Smith (2005) begins with a seemingly innocuous married couple. John and Jane Smith (played by Brad Pitt and Angelina Jolie) have a painfully boring marriage and frequently find themselves arguing in front of their perplexed marriage counselor—until the fateful day they discover they're both highly skilled assassins on a mission to kill the same target, of course. When their agencies find out, they become each other's next targets, instigating a massive shootout in their home. All the gunfire proves to be a powerful turnon for the lethal couple, because they end up having sex instead of killing each other. (Don't you hate it when that happens?) Their marriage renewed, the decide not to brutally murder each other—adorable. The only problem is that their agencies really, really want them dead and set out to complete the mission themselves. When you get two people this attractive in the same room, they're bound to rip their clothes off, which is exactly what happens, blissfully giving us a shirtless Brad Pitt sex scene that's bound to leave you hot and bothered. Who knew marriage could be so fun?