full size Pretty Little Liars Halloween Episode: The Girls Pose for a Pic
Credit: Richard Foreman/ABC Family Channel © 2010 Disney ABC Television Group

With the news that Pretty Little Liars will premiere its new web series Pretty Dirty Secrets immediately following the Season 3 summer finale (Season 3, Episode 12: “The Lady Killer,” airing August 28), we have a clearer timeline for when the highly anticipated Halloween episode (Season 3, Episode 13: “This Is a Dark Ride”) will air.

Pretty Dirty Secrets will have eight weekly episodes, starting on August 28. This should mean that the PDS finale will air on Tuesday, October 16. Since the series will take place in Rosewood’s Halloween store and leads up to the Halloween episode, it should follow that the Halloween episode will air on Tuesday, October 23, or sometime around then.

Are you ready for the scary-sounding episode? We know that it won’t be a prequel like Season 2, Episode 13: ”The First Secret,” and that Alison will make an appearance. But what are we to make of the chilling final page of the script?

Mark your calendars!

Catch an all-new episode of PLL on Tuesday, August 21 at 8 p.m. ET/PT on ABC Family.

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