‘Pretty Little Liars’ Spinoff ‘Ravenswood’ Adds New Regular (Exclusive)

ABC Family has added another Ravenswood resident.

Former Kyle XY and Supernatural actress Merritt Patterson has joined the Pretty Little Liars spinoff series Ravenswood, The Hollywood Reporter has learned exclusively.

Ravenswood centers on a town not far from Rosewood, Pa., that has suffered for generations under a deadly curse. Five strangers find themselves connected by the fatal curse and are charged with investigating the town's mysterious and terrible history before it's too late for everyone.

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Patterson will play the series regular role of Tess, Olivia's (Elizabeth Whitson) former best friend who is not involved with the curse. She'll appear in the subsequent Ravenswood episodes that follow the series' Halloween installments.

Pretty Little Liars star Tyler Blackburn, who plays Hanna's (Ashley Benson) significant other Caleb, will leave Rosewood and topline the new series as a regular. Blackburn will be seen traveling to the new town in the Halloween hour where he'll be joined by Brett Dier (L.A. Complex) and former model Whitson, who play twins Abel and Olivia, respectively.

Marlene King, Oliver Goldstick, Joseph Dougherty and Leslie Morgenstein are on board to executive produce Ravenswood, which like Pretty Little Liars hails from Alloy Entertainment and Warner Horizon Television.

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Patterson, whose credits also include Life Unexpected, the first version of the CW's The Selection pilot and Percy Jackson & the Olympians: The Lightning Thief, is repped by Play Management and Mosaic.

The series still has two female major roles to be cast, including the part of Miranda -- who will appear in the Halloween episodes -- as well as an unnamed character poised to join later in the series.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit

Lesley Goldberg , Philiana Ng