As refugees are found on the beach amid a number of dead bodies, they claim to be from a future where normal humans are facing genocide from a race of evolved humans.
Reece's story and how she turned against her own kind is revealed. A meeting with Emma turns into a trap that Reece barely escapes with her life. Leah's life hangs in the balance after she contracts an incurable disease.
Emma grows suspicious of Lindauer. A refugee, Hannah, sneaks out of the guarded zone and meets someone who has a connection to her future.
As Leah's condition deteriorates, Jude grows fearful that this may cost him his son's life. A dark secret is revealed about Hannah. Emma's investigation of a refugee from the earlier migration puts her life on the line.
The secrets of the earlier migration and the plot they are working on come to light. In order to save Leah, Sophie makes a decision that jeopardizes her career.
Lindauer derails Sophie's plans to save Leah and interferes with Jude's investigation. Marshall helps to expose the situation in the refugee camp to the public.
Caleb discovers that they have a mole in their midst. To placate Jude, Lindauer allows some refugees to go into town.
Paul's wife manipulates him into helping her plot. Lindauer takes advantage of Reece's captivity to run some tests. A so-called prophet emerges from among the refugees.
Jude stumbles onto a witness who reveals the history of the crossing and the identity of some of the First Arrivals. The cause of Lindauer's vendetta is revealed.
Sophie takes drastic action in an attempt to find a cure. Eve prepares to launch a deadly attack on the refugee camp. Marshall and Diana converge on the camp to help with the refugees' escape.
As the refugees enact their escape plan, Lindauer comes to realize how far Eve is willing to go to achieve her goal. Sophie deals with the aftermath of taking the cure. Jude discovers a startling connection to Naomi.