Kelsey honors her late mother by training for a marathon and sharing her journey online. Her posts attract Billy (Keenan Tracey), a grocery worker caring for his disabled mother, Debbie. Obsessed, Billy kidnaps Kelsey and hides her in their attic, controlling her for years. When Debbie discovers the truth, she and Kelsey must fight for survival.

Kelsey honors her late mother by training for a marathon and sharing her journey online. Her posts attract Billy (Keenan Tracey), a grocery worker caring for his disabled mother, Debbie. Obsessed, Billy kidnaps Kelsey and hides her in their attic, controlling her for years. When Debbie discovers the truth, she and Kelsey must fight for survival.