It's Always Sunny gang heads to Ireland in trailer for record-breaking season 15

Strap in, because TV is about to get sunny again.

After two years away, Charlie (Charlie Day), Mac (Rob McElhenney), Dennis (Glenn Howerton), Dee (Kaitlin Olson), and Frank (Danny DeVito) make their triumphant return in the trailer for season 15 of It's Always Sunny in Philadelphia. Upon the Dec. 1 premiere on FXX, Sunny, which is already renewed through season 18, will officially become the longest-running live-action sitcom, by season count, in American television history.

The new first-look footage reveals the gang's trip to Ireland, Mac's desire to become a Catholic priest so that God can be the only man to fill him up, and Frank's deceased partner.

"I was in business with Jeffrey Epstein," Frank tells his kids. "I was on the sex island. But only for the snorkeling!"

"This season was particularly fun also because we had 2019 and 2020 to write about, and so it's quite a season," Kaitlin Olson recently told EW. "I read the scripts and was squealing with delight; it's so much fun. We had a lot of good material out in the world. Our first episode is called '2020: A Year in Review,' and it's wild. [Laughs] People are going to love it and hate it."

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