Warning: This story contains mild spoilers for episode 6 of Pretty Little Liars: Original Sin.
The Pretty Little Liars and Riverdale universes are one and the same. In a recent episode of the new spinoff series Pretty Little Liars: Original Sin, the new Liars pay a visit to Rosewood, the location where the original series took place. They learn that several patients from the local sanitarium had been "sent to the Sisters of Quiet Mercy over in Riverdale." That's a clear reference to The CW's Riverdale in which the Sisters of Quiet Mercy is featured as a home for troubled youths and parentless children.
While he was not involved with the original series, Pretty Little Liars: Original Sin was developed by Riverdale creator Roberto Aguirre-Sacasa. In a new interview with TVLine, Aguirre-Sacasa, who also serves as executive producer and showrunner on Original Sin, has confirmed that the Riverdale reference was an acknowledgment that these two shows are part of the same universe. As Aguirre-Sacasa explains:
“I guess it does [mean the shows are connected]. We kind of just wrote that line in. I assumed that we wouldn’t be allowed to reference Riverdale, since it’s in a completely different universe, but it stayed in. So, yeah, I guess it does exist in the same universe. Bailee [Madison] gives a great look when that’s mentioned. That was obviously just a fun Easter egg in an episode with the biggest Easter egg of them all, which is going to Rosewood.”
If the Pretty Little Liars and Riverdale worlds are now linked, does that mean there could be more crossovers to see in the future? Aguirre-Sacasa is certainly open to it, as is at least one cast member who's also pushing for a rivalry between each show's respective local sports teams. But while Aguirre-Sacasa would love to mix these shows a bit more, he can't guarantee anything, as any plans could always potentially get vetoed by The CW or HBO Max.
“Alex [Aiono], who plays Shawn, is obsessed with the idea of a rivalry between the Millwood High Steppenwolfs and the Riverdale Bulldogs. I would love for there to be a football game between them. 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 be great, though, that’s for sure.”
Linking the Universes Creates a Continuity Error
It's interesting to think about Pretty Little Liars: Original Sin and Riverdale sharing a universe, as, by extension, each show's respective spinoffs are also included. The original Pretty Little Liars and its previous spinoffs, Ravenswood and The Perfectionists, would be included. The same can be said for the Riverdale universe shows, Chilling Adventures of Sabrina and the short-lived Katy Keene.
Here's where things get tricky, as Lucy Hale plays main roles in both Pretty Little Liars and Katy Keene. Secret twins are not all that uncommon in the Pretty Little Liars universe, so is that the case with Aria and Katy? Or do the two just happen to look exactly alike? In any case, executive producer Lindsay Calhoon enjoys imagining Hale playing both characters, however they want to explain it.
"I love a world where all of the shows come together, and Lucy Hale is in duplicate playing Katy Keene and Aria.”
You can find Pretty Little Liars: Original Sin streaming on HBO Max.