Romantic chemistry is all about warm, gooey feelings that gush from the deepest depths of the heart...right? Not quite. Actually, the real boss behind attraction is your brain, which runs through a very quick, very complex series of calculations when assessing a potential partner. Dawn Maslar explores how our five senses contribute to this mating game, citing some pretty wild studies along the way. [Directed by TOGETHER, narrated by Addison Anderson].