VIDEO: Sneak Peek - One of Liars Goes to the Dark Side on Next PRETTY LITTLE LIARS

On the next episode of PRETTY LITTLE LIARS, after being blackmailed by A.D, one of the liars begins to pass to the dark side to protect those closest to her. The episode airs Tuesday, May 16th on Freeform. Check out a sneak peek below!

About Pretty Little Liars: ROSEWOOD is a perfect little town. So quiet and pristine, you'd never guess it holds so many secrets. Some of the ugliest ones belong to the prettiest girls from town: Aria, Spencer, Hanna and Emily, four friends whose darkest SECRETS began to unravel after Alison, the queen bee of their group disappeared. As the mystery surrounding Ali's disappearance resurfaced, the girls began getting messages from a mysterious "A," who they quickly realized was out to get them. After years of tormenting and numerous shocking revelations, including the discovery that Ali is still alive, the Liars eventually UNCOVERED the true identity of their tormentor.

With "A" finally behind them, they are able to move on to the rest of their lives, without looking over their shoulders. Now, five years later, the girls have each pursued their own paths and have started adjusting to a life without "A," when something happens in ROSEWOOD that forces them to go back to where it all started. Torn between their old habits and their new lives, the events in ROSEWOOD compel the Liars to stick around, and together, as relationships are once again put to the test and SECRETS are revealed. Having matured over the past few years, these are not the same girls who left Rosewood. As new lies emerge - how will they push forward without going back?