Andy and April keep their bills in the freezer on 'Parks and Recreation,' but Dee has another solution on 'It's Always Sunny in Philadelphia,' Season 6 of which is available on DVD and Blu-ray today.

Her preferred mail storage option? The sewer. Which is why it's kind of surprising that Charlie and Frank stumbled upon it during one of their jaunts through the sewers. But, uh, why were they there in the first place? Check out AOL TV's exclusive clip from 'It's Always Sunny in Philadelphia: The Complete Sixth Season' and see for yourself ... or not