Pretty Little Liars is filled with mystery, and now there's yet another mystery to ponder as we wait for the Season 3 winter season.

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The cast and crew are currently filming Season 3, Episode 20. Yesterday (October 4), a fan asked PLL writer Andy Reaser which actors were on set filming, and he replied "Emily Ashley Hanna Paige CeCe Wren Wilden and a mysterious figure."

Long list! We're excited about the return of characters like Wren (Julian Morris), Wilden (Bryce Johnson), and CeCe, but we're particularly intrigued by the "mysterious figure."

Who do you think that is? Toby (Keegan Allen)? Another member of the "A" team? Someone in one of those creepy doll costumes? (Hey, we're just spitballing here!)

What do you make of this tweet? Why do you think Andy wouldn't share who that last person is? Let us know your theories in the comments below.

Find more Pretty Little Liars spoilers here.

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.

Source: @AndyReaser

Rebecca Martin is an editor at Wetpaint Entertainment. Follow her on Twitter @BeccaMartin47.

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