Obsessed with their virtual reality quest, Jin and Jack race to solve a complex riddle - but advancing to the next level brings harrowing consequences.

In a universe where Sierra is the undisputed ruler, Davey and Jonesie join the Resistance.

Reunited with his long lost father, Andy finally confronts Hugo about the missing money, only for them to wind up lost in the bush, while Cassie witnesses the shocking discovery of Gareth's body.

Helena makes allies in a treetop village, and travels to a Pteranodon den.

A missing woman, a dead stag - DI Riya Ajunwa knows something is not right in Chadder Vale. There must be a connection between the two, but what is it?

It's the team's most confounding puzzle yet when a passenger disappears from a flight to Dominica, only to be found back in Saint Marie - murdered.