It's Always Sunny in Philadelphia - Season 2 - Eps 5: Hundred Dollar Baby
Frank runs into an old adversary at the gym when he begins teaching Dee to box after she was robbed. Hoping to make some extra money on the side, Mac and Dennis make preparations for Charlie to compete in an underground street fighting match.
About It's Always Sunny in Philadelphia

Title: It's Always Sunny in Philadelphia
First Air Date: 2005-08-04
Last Air Date: 2023-07-19
Status: Returning Series
Rating: 8.3/10 (from 1128 votes)
Language: EN
Seasons: 17
Total Episodes: 169
Network: FX FXX
Genres: Comedy
Production Companies: 3 Arts Entertainment, Bluebush Productions, FX Productions, RCG Productions
Synopsis
Four egocentric friends run a neighborhood Irish pub in Philadelphia and try to find their way through the adult world of work and relationships. Unfortunately, their warped views and precarious judgments often lead them to trouble, creating a myriad of uncomfortable situations that usually only get worse before they get better.
Cast

Charlie Day
Charlie Kelly

Glenn Howerton
Dennis Reynolds

Rob McElhenney
Ronald 'Mac' McDonald

Kaitlin Olson
Deandra 'Dee' Reynolds

Danny DeVito
Frank Reynolds