How I Met Your Mother2005

Ted Mosby:
Look, there's a fine line between love and insanity. It's the Dobler-Dahmer theory.

Lily Aldrin:
Damn, I always forget the little one!

Ted Mosby:
All right. If both people are into each other, a big romantic gesture works. Like Lloyd Dobler holding up the boom box outside Dianne Court's window in Say Anything. But if one person isn't into the other, the same gesture comes off serial-killer crazy, or Dahmer.