'Pretty Little Liars': Special Halloween Episode to Air Later This Year (Exclusive)

Ashley Benson & Laura Leighton-Pretty Little Liars Still-2011
Danny Field/ABC

If the new season of Pretty Little Liars wasn't enough, a special holiday episode is on the way.

As a part of ABC Family's annual "13 Nights of Halloween" programming event, an original episode of the hourlong drama will premiere. So far, Pretty Little Liars is the only original scripted series to take part, but being that it is one of the network's buzziest shows, that isn't much of a surprise.

But the Halloween episode wasn't always in the cards. Executive producer Oliver Goldstick, who co-runs the show with Marlene King, revealed to The Hollywood Reporter, "We weren't planning this and then ABC Family came to us and said we'd love for you to do a one-off."

For production to maintain its shooting schedule (and finish on time in mid-December), it meant doubling up. "We truly have two crews running simultaneously. Episodes 207 and 208 are being shot at the same time," he says.

Goldstick added later: "We were already very tight at 24 episodes, now we're doing 25 from March to December. That's a lot of episodes."

But to get things done in a reasonable amount of time meant employing a filmmaking trick -- aside from the scheduling nightmare.

"We try to get these scripts done as quickly as possible so the ADs (assistant directors) could set a jigsaw puzzle and look at the actors' schedules because you have to shuttle Lucy Hale from one set to another within the hour," Goldstick explained. "We basically got some photo doubles for this episode. It's a little bit of block-and-shoot because you're going to shoot them out and then bring in a double who has the same hair in the back. That's how you have to do it otherwise you can't get the scene."

Because of ABC Family's move toward scripted (it currently boasts nearly a dozen original series on its slate), it made sense for the network to continue expanding its presence with its original series on "13 Nights of Halloween." Last year, the half-hour comedy Melissa & Joey aired a few episodes during "13 Nights."

"It actually lends to our show nicely as well," Goldstick says of the standalone, of which he wouldn't reveal the plot.

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Email: philiana.ng@thr.com