The survivors work out how to call for help - but are faced with a treacherous climb; as some of the group begin to crack under the pressure, a third death - the most violent so far - warns that they are running out of time.

Cast: Eric McCormack, David Ajala, Lydia Wilson, Adam Long, Jan Le, Siobhán McSweeney, Peter Gadiot, Carolina Guerra, Ólafur Darri Ólafsson