10. Notes on a Scandal (2006)
Being hot for teacher, fantasizing about hooking up with the smokin', glasses-clad temptress that makes it impossible to concentrate on your algebra notes is nothing out of the ordinary. Watching it actually play out on screen, though, between a weathered educator, Sheba Hart (Cate Blanchett), and her 15-year-old admirer (Andrew Simpson) is enough to put a kibosh on those daydreams fast.
While watching the two get after it over and over again, Letourneau-style, in various clandestine meeting spots can be a true test of your gag reflex, nothing can quite prepare it for the revelation that Sheba Hart is in the midst of an even more nightmarish love triangle than she thought, one in which Dame Judi Dench is the ultimate predator.