By Jethro Nededog
LOS ANGELES (TheWrap.com) - "Ravenswood" has two new residents.
ABC Family announced on Monday that Brett Dier and Elizabeth Whitson will join the "Pretty Little Liars" spinoff, which premieres in October.
Dier and Whitson will play fraternal twins, Abel and Olivia, who will make their first appearance on the "PLL" Halloween special, which will be followed by the "Ravenswood" premiere.
Abel is described as "a lone wolf with an old soul whose trust is hard won but who is loyal until the end." Olivia is "a once carefree and effortlessly happy spirit who has recently experienced hardship, leaving her questioning what's important and what no longer matters."
Dier, 23, played Brandon Kelly on the second season of Canadian series, "The L.A. Complex," in addition to several bit roles, which include The CW's "Secret Circle," "Supernatural" and "Smallville. Whitson will be joining the series after working as model.
The casting follows last week's news that "PLL" star Tyler Blackburn will be jumping over to "Ravenswood" as a regular cast member after he travels to the town on the upcoming fourth season Halloween special.
"Ravenswood" will center on a town, not far from "PLL's" Rosewood, Pa., which has suffered under a deadly curse for generations. Five strangers suddenly find themselves connected by this fatal curse and need to dig into the town's mysterious and terrible history before it's too late for each of them.
Both "PLL," which returns to ABC Family on June 11, and "Ravenswood" are produced by Alloy Entertainment in association with Warner Horizon Television. They're executive produced by I. Marlene King, Oliver Goldstick, Leslie Morgenstein and Joseph Dougherty.