"Beyond season 18, I don't know... it could quite possibly be the end," says the star and executive producer to THR about the longest-running live-action sitcom, now back with season 17.

The actors discuss playing best friends and roommates on FX's long-running comedy, which kicks off its 17th season Wednesday, and why "whenever Charlie does something, it titillates Frank."

Fans of both It's Always Sunny in Philadelphia and Abbott Elementary have eagerly been awaiting the second part of their comedy crossover, which audiences finally got to watch last night as the premiere episode of season 17,

Day and co-writer/star Rob Mac disagreed on whether or not cross over with "Abbott Elementary" and "The Golden Bachelor" in the new season

As “It’s Always Sunny in Philadelphia” enters its 17th season after nearly two decades, its team of writers/stars (Charlie Day, Glenn Howerton and Rob Mac) has become a well-oiled machine.

The new season of "It's Always Sunny in Philadelphia" premieres tonight at 9pm on FX. Why it matters: The Philly-based show, entering its 17th season, is the longest-running live-action sitcom on TV.

This one "It's Always Sunny in Philadelphia" episode riffed on pop culture in so many hilarious ways. In fact, it was seemingly inspired by "Jaws."

Charlie Day said he ‘would love’ to make a cameo in his wife Mary Elizabeth Ellis’ latest show, Netflix’s ‘A Man on the Inside,’ while chatting exclusively with PEOPLE at the ‘It’s Always Sunny in Philadelphia’ 20th anniversary celebration on July 1.