Teenager Regina "Red" DeWitt lives with her father, Cooper DeWitt, just outside New Orleans, Louisiana. Shortly after Red's mother abandons the family, both struggle to cope in their newfound roles. Red has become reserved and angry, while Cooper has descended into destructive alcoholism. But when a mysterious monster begins stalking their family home, the estranged duo soon realize that the secret to defeating the creature, and saving their future, may be in letting go of their past.