In the winter of 1982, four years after killing The Grabber, seventeen-year-old Finney Blake lives with his sister Gwen and their sober father Terrence. While Finney attempts to move on with his senior year, he suffers from panic attacks and nightmares. Gwen's psychic abilities have grown stronger, but they bring terrifying visions of a snow-covered retreat called Alpine Lake Christian Camp, where young boys vanished back in the late 1950s. When an old payphone on the side of a gas station rings with no wires attached, Finney hears a voice that chills him to the bone: The Grabber is back. Gwen learns that their late mother, Hope, worked as a camp counselor at Alpine Lake in 1977 right before her mysterious death. Convinced that the truth about their mother and The Grabber's earliest crimes is hidden in the mountains, Finney, Gwen, and their friend Ernesto travel to Alpine Lake during winter break. Upon arriving at the camp, a heavy blizzard traps the teenagers in the snowy wilderness. The camp handyman, Armando Mando Reyes, shares dark local legends about past disappearances. Soon, the camp's unplugged phones begin to ring throughout the empty bunkhouses. The ghosts of three young boys murdered in 1957 begin reaching out to Gwen in her dreams, warning her that The Grabber has found a way to bridge the world of the dead and the living. Finney and Gwen must uncover the frozen secrets buried beneath the ice before the killer claims them from beyond the grave.

In the terrifying climax, Gwen has a full psychic vision that uncovers the ultimate truth about her family. Their mother did not commit suicide as they had believed for years. In 1977, Hope discovered that the camp maintenance man was actually a young Grabber who had killed three boys and sunk their weighted bodies beneath the frozen lake. Before Hope could tell the police, The Grabber murdered her and staged the scene to make it look like a suicide. Because the bodies of his earliest victims remained hidden beneath the frozen lake, The Grabber maintained a supernatural anchor to the living world. Using this anchor, his vengeful spirit manifested at the camp, hunting Finney through the blizzard with a spectral axe. Armed with this knowledge, Finney and Ernesto brave the freezing storm to break open the ice of Alpine Lake, using diving gear to locate the long-lost remains and bring them to the surface. With the frozen corpses recovered, the ghosts of the three boys are freed from their watery graves. Joined by the loving spirit of Hope, the ghost boys hold The Grabber's spirit in place. Finney confronts the killer face to face on the icy dock, shattering his devil mask and severing his supernatural connection. The Grabber's ghost is dragged into the icy depths and banished back to Hell. As emergency sirens echo across the snow, Finney and Gwen embrace on the shore, finally free from the shadow of the killer and comforted by the knowledge that their mother was a hero who died trying to save children.