When a research scientist sneaks into Pretty Lake, the survivors must decide whether to trust his clinical trial for a possible cure.

1. Get Out of Town 43m When Adam convinces Wiley to escape, they learn whether they are truly contagious to outsiders. Chuck devises a daring escape plan of his own.

2. Us vs. Them 44m Liam must use science to prove his good intentions. When Renee reappears, Ronnie finds out what she really wants. Franny breaks away from Gord.

3. Hope 43m Ronnie discovers a commune of survivalists. Wiley is forced to make a heartbreaking choice about her son. Adam investigates Liam's background.

4. Extraction 43m Franny reviews security footage for answers. Recent events take a psychological toll on Chuck. To test the cure, Liam hunts for someone turning 22.

5. Horatio Rising 43m Adam seeks an outside expert to get the leverage necessary to force the government's hand. Renee makes a move to reclaim her command of the commune.