EXCLUSIVE: 'It's Always Sunny in Philadelphia' Stars Can't Keep It Together in Hilarious Blooper Reel

Bouts of uncontrollable laughter were bound to break out on this TV set.

It's Always Sunny In Philadelphia has been one of the funniest shows on television for over a decade -- and as it turns out, there are just as many laughs off screen.

In this exclusive look at the show's incredible gag reel -- a special feature on It's Always Sunny's season 10 DVD box set -- fans get a look at just how hard it is for the show's stars to keep a straight face when confronted with the hilarious, baffling lunacy that makes the FXX series so great.

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Although it’s not surprising to learn that when bringing together a group of hilarious friends for a raunchy, largely-improvised sitcom, you're bound to have some pretty solid bloopers -- or uncontrollable fits of laughter that ruin tons of takes.

The 10th season of It's Always Sunny in Philadelphia -- starring Charlie Day, Danny Devito, Glenn Howerton, Rob McElhenney and Kaitlin Olson -- is coming to DVD on Jan. 5, while season 11 premieres Jan. 6 on FXX.

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