On a routine prison transfer a veteran paramedic, Melina, awakens in her overturned ambulance with a vicious prisoner still strapped to a gurney. Gradually she is joined by a rag-tag group of survivors including a couple of police officers, another prisoner, and some paramedic colleagues. They soon realise that their vehicles have been crashed into a ravine in the forest deliberately. The highway – and freedom – is only 100 yards away but a murderous group of masked marauders is stalking them and has engineered events and hand-picked everyone there. But why were they chosen, what is the killers’ plan and who will survive the night?