05/15/2013 08:53 am ET

'Game Of Thrones' Writers David Benioff And D.B. Weiss Wrote 'Always Sunny' Episode

It's the crossover you never saw coming: "Game of Thrones" and "It's Always Sunny in Philadelphia." Well, sort of.

"Always Sunny" star Rob McElhenney tweeted a photo of him with "Game of Thrones" executive producers and co-creators David Benioff and D.B. Weiss on set of his FX comedy and revealed the duo wrote an episode for the upcoming season.

An FX spokesperson confirmed McElhenney's tweet. So expect dragons to invade Paddy's Pub sometime next season.

Benioff's other credits include "Troy" and "X-Men Origins: Wolverine."

The episode will air on FX's new sister network FXX, which is set to launch in early September with "Always Sunny" serving as an anchor series. When FX announced the move, the network also gave "It's Always Sunny in Philadelphia" an early Season 10 renewal.

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