The Perfectionists has been ordered as a series, to air on Freeform. 

As reported on Variety.com:

The series is a spinoff of “Pretty Little Liars” and has received a 10-episode order at the cable network with an expected debut in 2019. Freeform ordered a pilot for “The Perfectionists” in September with Sasha Pieterse and Janel Parrish set to star. “Pretty Little Liars” showrunner I. Marlene King wrote the pilot and served as executive producer with Lisa Cochran-Neilan, Leslie Morgenstein, Charlie Craig, and Gina Girolamo. Alloy Entertainment and Long Lake Media produce in association with Warner Horizon Scripted Television. Elizabeth Allen Rosenbaum directed the pilot.

Sasha Pieterse and Janel Parrish will reprise their roles as Alison DiLaurentis and Mona Vanderwaal. This is being seen as a spin-off of Freeform’s previous hit TV show Pretty Little Liars, when in fact, The Perfectionists will be based on a book, also by Sara Shephard, but set in an entire different setting. The idea to merge the two worlds was born after Pretty Little Liars signed off after seven seasons.

You can watch the trailer and read the synopsis of the book below.

Synopsis:

Ava, Caitlin, Mackenzie, Julie, and Parker are all driven to be perfect—no matter the cost.

At first the girls think they have nothing in common, until they discover that they all hate the same person: handsome womanizer Nolan Hotchkiss, who’s done things to hurt each of them.

They come up with the perfect plan to murder Nolan—jokingly, of course. They’d never actually go through with it. But when Nolan turns up dead in the exact way they’d discussed, the girls suddenly become prime suspects in his murder.

Only, they didn’t do it.

So who did? Unless they find the real killer, and soon, any one of them may be the next to die….