It’s Always Sunny in Philadelphia Season 4 Episode 7

Charlie and Frank awake to find poop in their bed. Neither will confess to being the owner, so they, Mac, and Dennis try to scientifically deduce who dropped the deuce. Dee wants to do something a bit more sophisticated, so she invites the waitress and Artemis to a girls’ night out.

Episode Title: Who Pooped the Bed?

Air Date: 2008-10-09