“To our Mom” is the unlikely dedication siblings Andy and Barbara Muschietti leave at the end of the supernatural “Mama.” Director Andy expands “Mama,” a one-scene three-minute short he wrote and directed, with his sister as producer , in 2008: a scary freak of a mother-figure chases little Lilly and Victoria around their house. In the pre-credits setup to this workable, if unremarkable horror tale we see the sisters at ages one and three. A radio news report on a nationwide “panic” mentions a Manhattan finance exec, Jeffrey (Nikolaj Coster-Waldau), shooting two colleagues at the office, driving home, shooting his wife, and then driving away with their daughters. An exceptionally well-staged crash scene shows his car skidding off a snowy mountain road in Virginia. Jeffrey leads his daughters to an abandoned cabin. How the two girls spend the next five years is detailed by their drawings during the opening credits. Jeffrey’s alternative-comics brother Lucas (also played by Coster-Waldau) and his punky rocker girlfriend Annabel (Jessica Chastain) get custody, with the help of a psychiatrist keen on studying the feral sibs who subsisted on black cherries and who walk on all fours. Annabel is not mom material, at first. She is but one of the women in “Mama” who will attempt to protect Victoria (Megan Charpentier) and Lilly (Isabelle Nelisse). One stabbed a nun at St. Gertrude’s Asylum in 1878. Another one seeks evidence of abusive bruises to report to child services. Javier Botet (who plays a recurring character in the “[REC]” horror series) plays the gaunt, disjointed ghost with very spooky hair who hides in walls, metamorphoses into black moths and makes a flashlight and fluorescent lights flicker, and can even input its name on a vital signs monitor in the intensive care ward. Fans of “Mimic,” directed by “Mama”‘s executive producer Guillermo del Toro, may like how the seven-foot tall Mama emits the same clicking sounds as the seven-foot-tall cockroaches in that 1997 horror film with its own motherhood issues. 100m. (Bill Stamets)
“Mama” opens Friday.