Lately, Pretty Little Liars has seemed a little too … sane. Well, other than our boy, Toby (Keegan Allen) and, of course, Mona (Janel Parrish). Perhaps it’s because a certain someone has been missing. Someone fairly close to the girls. Someone we don’t quite trust. Yep, we’re talking about Dr. Sullivan (Annabeth Gish).

We knew she was returning, but it’s a new little something about her return that has suddenly piqued our interest.

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PLL showrunner Marlene King recently tweeted, “Watching 318. The return of Doctor Sullivan makes me very happy!”

So, the good/bad doctor will be back in Season 3, Episode 18, and her return makes Marlene feel (of all things) happiness? Does that mean her return could be good? We suppose that depends on how you define good.

We’re thinking it’s one of two things: Her return is actually a good, as in pleasantly positive, thing for the Liars. Maybe Dr. Sullivan will restore some sanity and order to the town (if that’s possible). Maybe she’ll even defend the Liars and help them bring down the “A” team. After all, the doctor has spent a lot of time with Toby and Mona — Could she know their secret?

Or there’s option two: Marlene’s happiness is related to the good television created by her return, AKA the drama. Maybe all the time Dr. Sullivan has spent with Toby and Mona means she’s on their side? Or there’s always the not-yet-denied theory that she’s actually Mama Cavanaugh.

What do you think it is about Dr. Sullivan’s return that makes Marlene so happy? Could she be a part of the end-of-season drama involving Jason (Drew Van Acker) and company?

Let us know your theories for her return in the comments below!

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: @imarleneking

Samantha Highfill is a contributing writer to Wetpaint Entertainment. Follow her on Twitter at @samhighfill.

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