Pretty Little 'Halloween' Liars -- PICS & Promo!

Ashley Benson gets into the groove in this new still from the Pretty Little Liars Halloween special.

In “The First Secret,” It’s the Halloween before Alison (Sasha Pieterse) went missing and the only concern for Aria (Lucy Hale), Emily (Shay Mitchell), Hanna (Benson) and Spencer (Troian Bellisario) is to score an invite to Noel Khan’s Halloween party.

But with a new girl in town to challenge Ali for Queen Bee dominance, Spencer possibly losing the class president election along with her parents’ approval, and a shocking revelation for Aria about her father �” there may be more to worry about than finding the perfect costume.

With all of the tricks and treats floating around Rosewood, there may be something more sinister waiting out there for Ali and her best friends.

“The First Secret” premieres Wednesday, October 19th @8PM ET/PT on ABC Family. 35+ pics inside…