A group of strangers find themselves imprisoned in a house. Unsure of why they are there or who is behind it, they are soon enlightened by a video advising them there is a way out. But the threshold they must cross in order to escape is one of excruciating pain and - in the face of torture - not everyone is willing to play by the newly created rules, as they are soon ripped apart by infighting, secret alliances, double-crosses and shattering outbursts of violence, and with the clock ticking down, the "one for all" mentality devolves. Just how far will each of them go to survive?