Christopher Robert Cargill (born September 8, 1975) is an American screenwriter, novelist, podcast host, and former film critic known under the pseudonyms Massawyrm (on Ain't It Cool News) and Carlyle (on Spill.com). Cargill currently resides in Austin, Texas with his wife. He is best known for writing the films Sinister (2012), Sinister 2 (2015), Doctor Strange (2016), and The Black Phone (2021). He is a frequent writing collaborator of Scott Derrickson.