Eternal Moonshine of the Simpson Mind is the nineth episode of Season 19, which aired on December 16, 2007. The episode was written by J. Stewart Burns and directed by Chuck Sheetz.
Homer wakes up to find himself outdoors and covered in snow, without memory of the night before. When he arrives home, he finds everyone missing. Seeking help from Moe and Professor Frink, Homer tries to piece together his memory to find out what happened to him.