Guillermo del Toro presents Mama, a supernatural thriller that tells the haunting tale of two little girls who disappeared into the woods the day that their parents were killed. When they are rescued years later and begin a new life, they find that someone or something still wants to come tuck them in at night.

Five years ago, sisters Victoria and Lilly vanished from their suburban neighborhood without a trace. Since then, their Uncle Lucas (Nikolaj Coster-Waldau) and his girlfriend, Annabel (Jessica Chastain), have been madly searching for them. But when, incredibly, the kids are found alive in a decrepit cabin, the couple wonders if the girls are the only guests they have welcomed into their home.

As Annabel tries to introduce the children to a normal life, she grows convinced of an evil presence in their house. Are the sisters experiencing traumatic stress, or is a ghost coming to visit them? How did the broken girls survive those years all alone? As she answers these disturbing questions, the new mother will find that the whispers she hears at bedtime are coming from the lips of a deadly presence.