After seeing that creepy baby monster costume in the most recent webisode of Pretty Dirty Secrets, we had to wonder: Who are all the people who have hid behind that same mask on Pretty Little Liars, and how are they linked?

The first time we ever saw the creepy costume was in Season 2, Episode 13: ”The First Secret”, when Alison (Sasha Pieterse) is wandering around the Rosewood costume shop looking for her Lady Gaga costume. Someone wearing the baby monster mask creeps up behind her and gives her a scare, but never reveals himself (or herself).

Next, someone wearing the baby monster mask appears in Spencer’s (Troian Bellisario) backyard while the Liars are getting ready for Noel‘s (Brant Daugherty) Halloween party. They freak out, but when they look again, the masked spy is gone.

Then Alison claims that the same person in the baby monster mask attacked her in the empty house (outside of which a van from Radley Sanitarium had been parked earlier that day), where the Liars go to try and rescue her after a frantic text. After they find her, Ali claims it was just Noel pretending to attack her so the girls could prove their loyalty.

Later, Alison finds Noel back at his party and tells him he was a little rough during the prank. He claims that he actually got stuck at the party and couldn’t make it, which means that someone else wearing that baby mask attacked Ali for real. In the next scene, we see Lucas (Brendan Robinson) take off the mask, meaning it must have been him... right?

Nope! In the final scene, at least five other baby monsters are seen in the crowd at Noel’s party. Fast-forward to Pretty Dirty Secrets Episode 5, where Lucas secretly meets someone dressed in the same costume to trade information, or possibly money.

Finally, in this promo for the upcoming Season 3 Halloween episode (Season 3, Episode 13: “This Is a Dark Ride,” airing October 23), someone wearing the same costume sneaks up behind Spencer at the Ghost Train party and grabs her, covering her mouth to keep her from screaming. 

Do you think all those baby mask-wearing strangers at Noel’s party were all on the “A” team — and still are? If so, will we see Toby talking to one of them in the Halloween episode? Or maybe, if we’re lucky, one of them will take their mask off for once?

Don’t miss the next new episode of PLL, the Halloween special, on Tuesday, October 23 at 8 p.m. ET/PT on ABC Family.

Catch the next webisode of Pretty Dirty Secrets on Tuesday, September 25 at 9 p.m. ET/5 p.m. PT on ABCFamily.com.

Molly Friedman is an editor at Wetpaint Entertainment. Follow her on Twitter @MollyFriedman.

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