Peter Cornwell is directing the horror thriller, which revolves around two brothers (Riggs, Courtney) who go with their mother to take care of their grandma. Unbeknownst to them, the grandmother is a witch, who made an evil deal using black magic years earlier.

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Frances O’Connor is on board to play the mother.

Mercy is based on King’s short story Gramma, which was first published in Weirdbook magazine in 1984.

Jason Blum and Wonderland's McG and Mary Viola are producing. Matt Greenberg wrote the script.

On zombie drama Walking Dead, Riggs plays Carl Grimes, the son of sheriff Rick Grimes. The character this season has become an integral part of the storyline, which has allowed Riggs to show off his chops (both literally and figuratively). He is repped by the Burstein Co.

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Courtney made his acting debut starring in J.J. Abrams’ Super 8, coincidentally also playing the son of a sheriff. He recently wrapped a turn in in the indie drama Tom Sawyer & Huckleberry Finn, portraying Sawyer. He is repped by CAA Principato Young Entertainment and Felker Toczek.

Email: Borys.Kit@thr.com

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