Mac and Charlie head over to Dennis' old fraternity to pull a Good Will Hunting and embarrass the frat boys but get caught up with some sorostitutes.
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It's Always Sunny in Philadelphia Season 5 Episode 12 Quotes

Dee: Who slams a door?
Frank: Babies.
Dennis: That guy has some real growing up to do. Have some repect for Christ's sake... I am legend.

Charlie: I'll totally pull a Good Will Hunting on those kids and that'll put them in their place.
Mac: How you gonna do that?
Charlie: Well, you've seen the movie right?
Mac: Yeah.
Charlie: So all I gotta do is, I'll ask them some big shot, like math or science, history-type college question aand that will totally stump them by knowing a lot more about the answer than they do.
Mac: In that movie, Matt Damon played a genius janitor, you're just a janitor.
Charlie: Right, you stumped me with that one.