While on a road trip to visit her boyfriend in Montana, Danielle Sullivan and her sister Grace are kidnapped by a truck driver on a remote part of the highway, setting off a chain of events that leads private detectives Cody Hoyt and Cassie Dewell to team up with Cody's estranged wife and ex-cop, Jenny Hoyt, to search for the sisters. But when the investigators discover these are not the only girls who have disappeared in the area, it's clear they've stumbled onto something much bigger than them all.