MercilessMarlene King, creator and showrunner of the hit ABC Family teen series Pretty Little Liars, will adapt and executive produce The Merciless, a feature film based on the upcoming Danielle Vega horror novel about good girls gone evil. Lionsgate has acquired rights to the book ahead of its June 12 street date via Razorbill Books. Alloy Entertainment packaged and will produce the film, with Alloy president Les Morgenstein and Alloy Features VP Elysa MarleneKingDutton serving as producers. The deal reteams King and Alloy, which serves as a producer on Pretty Little Liars. The book centers on a new girl at a small-town high school who is taken in by the popular clique, only to have them compel her into joining them in a dangerous exorcism of a punky, rebellious classmate.

“I’ve had a great time collaborating with Les Morgenstein and Alloy on Pretty Little Liars and have enjoyed the thrill of scaring millions of teenagers every week,” said King in a release announcing the acquisition. “I intend to be merciless with the script and hope our audience will need to sleep with their lights on after seeing the movie.”

Lionsgate Motion Picture Group co-president Erik Feig is overseeing Merciless for the studio along with EVP Production & Development Gillian Bohrer and Director of Development Jina Jones. The deal was negotiated by Morgenstein on behalf of Alloy with Robert Melnik, Lionsgate’s EVP Business Affairs.

King, whose feature credits include Now And Then and the 2006 Lindsay Lohan-Chris Pine teen pic Just My Luck, is repped by WME.

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