Some of our favorite long-running cable series will be returning very soon, with FX and FXX revealing the fall return dates for "American Horror Story" and "It's Always Sunny in Philadelphia," as well as the premiere dates of several other shows.

First up is "American Horror Story," whose upcoming eighth season will be a crossover of "AHS" season one, "Murder House," and season three, "Coven." We still don't have a title, but we do know when it will debut: Wednesday, September 12.

Another lingering mystery was the fate of Dennis Reynolds on FXX sitcom "It's Always Sunny in Philadelphia," which saw the character -- played by Glenn Howerton, who's currently busy starring on NBC series "A.P. Bio" -- consider leaving Philly to parent a child he didn't know he had. It looks like that is indeed what's happening with Dennis, based on a new season 13 synopsis:

"The Gang the 13th season of the FXX original comedy series 'It's Always Sunny in Philadelphia.' Mac (Rob McElhenney), Charlie (Charlie Day), Dee (Kaitlin Olson) and Frank (Danny DeVito) return to their duplicitous, scheming ways at Paddy's Pub, while Dennis (Glenn Howerton) takes on the new role of father in North Dakota. Last season, the Gang experienced new highs — Mac acknowledged his sexuality and Charlie convinced the Waitress, his longtime target of affection, to move in with him — and the lowest of lows — Frank became the official beverage sponsor of a terrorist group, Dee helped a man reach rock bottom, and Dennis was investigated for murder.

"Even without Dennis Reynolds, the Gang has its hands full as Charlie hopes to have a child with the Waitress, Mac sets out to understand his newfound sexuality, Dee takes feminism to new heights, and Frank goes to great lengths for the Gang to experience the greatest moment in Philadelphia sports history — an Eagles Super Bowl victory."

Looks like that trip the cast took to the Super Bowl might actually end up appearing in an episode. The new season drops on Wednesday, September 5.

Here's the entire FX and FXX schedule for Fall 2018 so far:

FX: 10 p.m.: Mayans MC (NEW SERIES)

FXX: 10 p.m.: It's Always Sunny in Philadelphia (Season 13)

FX: 10 p.m.: American Horror Story (Season 8)

FX: Date/Time TBD: Mr. Inbetween (NEW SERIES)

The fifth and final season of FXX comedy "You're the Worst" is still waiting on a premiere date, as is the third season of FX's "Better Things."

[h/t TV Insider]