Eight-year-old Lester and his ten-year-old brother Connor Slade are spending a weeklong vacation with their wildlife conservationist uncle, Aaron Slade, who lives alone in a cabin in the middle of the woods. After finding out that the forest may also be home to Momo, a dreadful monster who has been stalking the Missouri forest for decades, the brothers decide to go monster-hunting and prove Momo's existence. Armed only with a flashlight and their guts, Lester and Connor follow clues that take them deeper into the woods and closer to something dark and sinister. What will the Slade brothers find in the frightening forest?