While sex scenes sometimes make for particularly memorable movie moments, threesome scenes are an entirely different ballgame, and, arguably, have a more lasting effect. Take, for example, the one in American Psycho. That bizarre scene where Christian Bale has a threesome while schooling two prostitutes in Phil Collins trivia isn't likely to be erased from the memory of anyone who's seen it.

This Friday, On the Road, starring Garrett Hedlund, Kristen Stewart, and Sam Riley, will show the rest of the world why they deserve to join American Psycho on this list of unforgettable three-ways in film history. But where do theirs rank among the scenes that came before them? You're about to find out.

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