One of the spoiler photos from Pretty Dirty Secrets, the Pretty Little Liars web series that will show a brief glimpse of what’s going on in Rosewood before the Halloween episode (Season 3, Episode 13: “This Is a Dark Ride”, airing October 23), features a mysterious brunette dressed in a creepy pink and white costume straight out of the Helena Bonham Carter/Tim Burton collection.

Just like the mystery of the Black Swan in Season 2, and the scary baby monster masks in the last Halloween episode (Season 2, Episode 13: ”The First Secret”), we’re dying to know who is wearing this demented doll get-up.

We already know what the Little Liars are wearing to the Ghost Train party, and we saw in this sneak peek that Jenna (Tammin Sursok) will be wearing an eye patch and a less elaborate costume. So who does that leave?

There’s Melissa (Torrey DeVitto), who we could definitely see showing up suddenly in this episode. Could she be obeying someone’s instructions just like she did at the masquerade ball? We would suspect Mona (Janel Parrish), but Mona’s hair is darker than the demented doll’s. Also, neither of them are listed in the official Pretty Dirty Secrets cast. Either way, we’re sure that we’ll see this mystery person and her costume in the Halloween special in October.

Tell us who you think this is in the comments!

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 18 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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