ENTERTAINMENT
08/01/2011 10:31 am ET Updated Oct 01, 2011

Fat Mac 'It's Always Sunny In Philadelphia' Teaser Trailer (VIDEO)

Mac is having a nightmare. And it's hilarious for everybody else.

Rob McElhenney gained 50 pounds for the new season of "It's Always Sunny In Philadelphia," with his massive weight gain first revealed in a fan photo earlier in the summer. Now, a teaser for the season has been revealed, with the star's expanding waistline a true horror sequence for his very vain character, Mac.

McElhenney explained his reason for weight gain to Collider:

"I was watching a very popular sitcom and noticing about how the characters were getting better looking, as the seasons progressed," he said. "And, I have never seen a sitcom in which the actors progressively got worse looking, which is, I think, truer to life, especially the lives that these characters lead. And, a character that's always talking about putting on mass and all he does is eat shit and drink beer would eventually look like this. I thought that would be an interesting experiment, and it seems to be working out."

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