Pretty Little Liars: Original Sin Revealed to Share Same Universe With Riverdale

A scene in the new series Pretty Little Liars: Original Sin suggested that the series actually shares a continuity with Riverdale, The CW's dark and twisted take on the Archie Comics characters. Some characters left Millwood for Rosewood (the setting of the original Pretty Little Liars), where they meet with Eddie Lamb (a character from that show, although here he's played by Charles Gray, rather than Reggie Austin). He informed them that a number of the patients from Rosewood's Radley Sanitarium were "sent to the Sisters of Quiet Mercy over in Riverdale" when Radley itself was converted into a hotel. 

The Sisters of Quiet Mercy was a strict religious order, where Betty Cooper's sister Polly was sent after she became pregnant. What started as a fairly traditional reformatory for wayward youths eventually evolved into an abusive prison-like establishment where the girls held there were abused.

TVLine took the initiative, asking executive producer Roberto Aguirre-Sacasa (who works on both shows) whether they share a universe.

"I guess it does," Aguirre-Sacasa replied. "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."

The logline for the series reads: "Twenty years ago, a series of tragic events almost ripped the blue-collar town of Millwood apart. Now, in present day, a disparate group of teen girls — a brand-new set of Little Liars — find themselves tormented by an unknown Assailant and made to pay for the secret sin committed by their parents two decades ago...as well as their own. In the dark, coming-of-age, horror-tinged drama PRETTY LITTLE LIARS: ORIGINAL SIN, we find ourselves miles away from Rosewood, but within the existing Pretty Little Liars universe — in a brand-new town, with a new generation of Little Liars."

Pretty Little Liars: Original Sin is now streaming on HBO Max.