Pretty Little Liars and Riverdale exist in the same universe, because sure, why not

On the newest episode of Pretty Little Liars: Original Sin — a spinoff of the 2010 Freeform show — the characters return to Rosewood, the town from the first series. It’s there that the main characters learn that some of the patients from Rosewood’s Radley Sanitarium were “sent to the Sisters of Quiet Mercy over in Riverdale.”

Yes, that Riverdale! The Riverdale that is the center of the CW’s Riverdale, the show that put a nitty-gritty spin on the Archie comics characters. The show that started out as standard murder mystery, but then became serial killers and cults and magical powers and alternate universes, with the most recent season ending with a comet hurtling towards town and catapulting everyone back to the 1950s.

It’s official: iconic teen thriller Pretty Little Liars and iconic teen paranormal-crime-drama-soap-opera-musical(?) Riverdale now share a universe.

To be fair, the connection isn’t so much a deliberate long con as it is executive producer Roberto Aguirre-Sacasa’s little Easter egg that ends up opening a whole box of Peeps (trying to connect two metaphors here, bear with me). As Aguirre-Sacasa told TV Line, he wasn’t even sure if he could make that connection.

“I assumed that we wouldn’t be allowed to reference Riverdale, since it’s in a completely different universe, but it stayed in,” he said. “So, yeah, I guess it does exist in the same universe.”

He went on to describe some in-jokes within the cast, with Alex Aiono apparently really into the idea of a football rivalry between the two high schools in both shows.

“I would love for there to be a football game between them,” Aguirre-Sacasa said. “Who knows, though. If we did push it further, I don’t even know how far we’d be allowed to push the shared universes. It would great, though, that’s for sure.”

The original Pretty Little Liars was based on a series of books by Sara Shepard and ran for seven seasons on Freeform (then known as ABC Family). It followed four estranged friends after a mysterious stalker starts sending them threatening messages about their deep dark secrets. The show eventually deviated far from the original book series, creating an incredibly tangled web of intrigue. You might say that Pretty Little Liars walked so Riverdale could catapult itself out of a cannon.

Pretty Little Liars: Original Sin premiered earlier this summer on HBO Max. It’s the third Pretty Little Liar spinoff, though the other two didn’t last long. Original Sin (which is, confusingly, not the original show) follows a different set of characters in a different town — till this episode, when they visited Rosewood and met up with a character from the original series (albeit, played by a different actor).

Riverdale has already crossed over with The Chilling Adventures of Sabrina, though that connection is a little easier to explain. After all, Sabrina is an Archie comics character. If Aguirre-Sacasa does decide to push the connection, there is one little itty bitty hiccup: Lucy Hale, who starred as artsy Aria Montgomery in Pretty Little Liars, also starred as Katy Keene in the Riverdale spinoff of the same name. And Katy Keene already made a Riverdale appearance.

But that doesn’t deter executive producer Lindsay Calhoon Bring, who told TV Line she would “love a world where all of the shows come together, and Lucy Hale is in duplicate playing Katy Keene and Aria.”

The original author of the Pretty Little Liars books, however, has yet to weigh in. The next thing to figure out: Where does Glee fit into this?