Guillermo del Toro's pappy McPoyle character on It's Always Sunny In Philadelphia character Pappy McPoyle is another hilarious and bizarre aspect of the comedy series. It's Always Sunny In Philadelphia follows the depraved adventures of Paddy's Pub gang Charlie, Mac, Frank, Dennis, and Dee. They're all varying degrees of awful while making the lives of those around them worse simply through their destructive and self-obsessed actions. The flaws and foibles of the gang are, however, nothing compared to the McPoyle's — and the head of the most gross-out family on TV is played by a very familiar face.

While the show may mostly revolve around the central gang, the It's Always Sunny in Philadelphia cast is also filled with plenty of memorable supporting characters too. Maybe It's Always Sunny In Philadelphia's best — or at least the grossest — recurring characters are the McPoyle twins Liam and Ryan. These twins come from a "pure," inbred family who loves milk and has terrible skin conditions. As the show has gone on, viewers have been introduced to the extended McPoyle family which eventually included the patriarch Pappy McPoyle. What's not immediately obvious about Pappy McPoyle, however, is that the character is played by Oscar-winning filmmaker Guillermo del Toro.

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Guillermo del Toro Plays Pappy McPoyle — The Patriarch Of An Inbred Family

Pappy McPoyle sitting on the stand in a courtroom in It's Always Sunny in Philadelphia

Pappy McPoyle is Liam and Ryan's grandfather and is first introduced in It's Always Sunny In Philadelphia season 8's episode "The Maureen Ponderosa Wedding Massacre," where he rambles to the gang about his babies springing from his loins fully formed, and when one tried to eat him, he ate the baby first. He later reappeared in season 11's "McPoyle Vs. Ponderosa: The Trial Of The Century," where he's called to the stand by Charlie. The Lawyer is suing Bill Ponderosa on behalf of Liam McPoyle, who lost his eye after the former spiked the wedding milk back in season 8.

Charlie calls Pappy to the stand who again rambles nonsensically before Charlie removes his hat to reveal Royal McPoyle, Pappy's pet bird who lives on his head and is responsible for gouging out Liam's eye. The trial ends in chaos and Pappy then orders Royal to gouge out The Lawyer's eyes and bring them to him. That's the last time Pappy McPoyle appeared on It's Always Sunny In Philadelphia.

While del Toro might seem like a surprising choice to guest star on It's Always Sunny in Philadelphia, it was surprisingly easy to arrange thanks to the friendship formed between del Toro and Charlie Day, who is one of the show's co-creators and plays Charlie Kelly. The two met during the making Pacific Rim. In a behind-the-scenes video detailing the cameo, del Toro reveals that when he was approached with the ideal of appearing on the show, he claims "I told Charlie to give me the most demeaning cameo he could in the episode, and he came up with Pappy McPoyle."

The McPoyles Are Returning (But No News On Guillermo Del Toro)

Ryan and Liam McPoyle sitting on a bed in It's Always Sunny in Philadelphia

Ever since his last appearance, fans have been waiting for a Guillermo del Toro It's Always Sunny in Philadelphia return as Pappy McPoyle. With It's Always Sunny in Philadelphia already underway, it is confirmed some of McPoyle family will return for at least one episode as Liam and Ryan return. Unfortunately, there is no news on whether Guillermo del Toro's Pappy McPoyle will return with them. Though del Toro was already a celebrated filmmaker by the time he appeared on It's Always Sunny, he has since become a three-time Oscar winner with movies like The Shape of Water and Pinocchio. Interestingly, Guillermo del Toro cameoed on Barry in its final season, showing that he's not adverse to TV acting roles, and might be open for a return on It's Always Sunny in Philadelphia.