At the end of Season 11 of It’s Always Sunny in Philadelphia, the gang drowned in the brig of a cruise ship and went to hell. Ten months later, at the start of Season 12, they were back in Philadelphia, very much alive and trapped inside a Wiz-like musical about racism in “The Gang Turns Black.” In 12 seasons, Always Sunny has never been concerned with narrative continuity — hammering home the main point of the show, that this group of people is incapable of growing or learning, has always been more important. If Always Sunny wrote itself into a corner, it just hit the restart button. But in the Season 12 finale, Dennis (Glenn Howerton) turning off the lights and walking out of Paddy’s Pub like he was Sam in Cheers feels different.

“Dennis’ Double Life,” in which the gang is introduced to a family it didn’t know Dennis had, is self-referential in a conclusionary way — not as overtly as Seinfeld’s series finale, but with similar vibes. The mother of Dennis’s love child hails from North Dakota; the two met and had sex when Dennis bailed on the gang’s trip to L.A. in “The Gang Beats Boggs.” Dennis’s name in his second life is Brian LeFevre, the moniker of the man who was murdered (possibly by Dennis) outside of Paddy’s in “Frank’s Back in Business.” A Thunder Gun Express poster can be seen at one point. At the end of the finale, Tom Tom Club’s “Genius of Love” plays (recall: “The Gang Squashes Their Beefs”) while Mac, Charlie, Frank, and Dee break out signature dance moves from past episodes. The episode is like a retirement party, and it’s hard not to take Dennis seriously when he says, “I can’t do any of this shit anymore.” Plus, Howerton himself said he might be leaving.

“It’s a little complicated,” he told Alan Sepinwall hours before the finale aired. “I might be [leaving], but I might not be … It has nothing to do with my relationship to anyone on the show or Rob [McElhenney] or Charlie [Day] or anyone like that. It’s partially a creative and personal decision.” Just as these comments from Howerton came out (he also gave a similar interview to The Wrap), Variety reported that Howerton had been tapped to star alongside Patton Oswalt in an NBC pilot produced by Lorne Michaels and Seth Meyers.

I can’t believe I’m writing this, but Dennis might actually be gone. And with two seasons still to come, Sunny fans might actually need to get used to seeing the rest of the gang without their vain, sociopathic friend.

In most episodes, Dennis plays Sunny’s straight man, the character who yanks his hair out when Mac or Charlie gives in to his absurd instincts, the one who admonishes Frank for dating a prostitute or frankly tells Dee that her acting dreams died years ago. He’s smarter than the rest of the group and ostensibly more attractive (though not more well-adjusted), but instead of finding a more appropriate group of peers, he preferred to slum it with the gang and feed his self-righteousness. If he’s gone — if there’s no one around to judge the other four — it’d make sense for the group to get even weirder, grosser, and more oblivious to societal norms. Look at Episode 8 of this most recent season, “The Gang Tends Bar,” which now feels like Part 1 of “Dennis’ Double Life.” All Dennis wants is for Mac, Charlie, Frank, and Dee to do their jobs, but the second any of them are out of his eyesight they’re on to manipulating and poisoning each other. Dennis often pulls the gang out of a crevasse, and it’s usually funny — but it might be even funnier to see what happens when there’s no one there to play the moral compass.

Dennis’s departure may also allow Always Sunny to toy with a new concept: the characters actually experiencing loss. For so long, the show has thrived on pushing the boundaries of the gang’s indifference — they once trapped a dozen or so people in a burning apartment without batting an eye — and now maybe it’s time to see them unzipped and overwhelmed by basic emotions. And then, in trademark Always Sunny fashion, just as the four characters move through the five stages of grief and approach normalcy, the show could press the restart button once more. It’d be their most irreverent stunt yet.

It’s Always Sunny in Philadelphia can still be a good comedy without the Dennis character. It’s the potential loss of Howerton as a producer and writer for the show that will hurt the most. Howerton has written or cowritten some of Always Sunny’s tightest episodes: “Mac Bangs Dennis’ Mom,” “Reynolds vs. Reynolds: The Cereal Defense,” and “The Gang Hits the Road.” Alongside fellow executive producers McElhenney and Day, Howerton’s intricate understanding of the show’s characters has allowed him to pen clever installments that transcend their immature premises. He’s been able to express the inner workings of these deviants without ever using exposition as a crutch, tricking viewers into falling in love with Always Sunny’s characters even as they don blackface or dump garbage in an inner city neighborhood.

For Always Sunny, Howerton isn’t replaceable. He’s ingrained in the show’s DNA; whatever happens next without him won’t be the same show that audiences have tuned in to for 12 seasons now. But change and adversity could also mean opportunity. As unexpected as Howerton’s departure might be, it gives Always Sunny myriad new paths to walk down. FXX has two more seasons of the show on the docket. The end is near, but for now, it’s time for Always Sunny to get real weird with it.