Duke and Nathan are sent back in time to 1955, and Audrey is the only one who realizes that their actions are having serious consequences in present-day Haven.
As attempts are made to stop William, things only get worse. A search begins to find the fourth key person for opening the gateway. Audrey continues the fight to remain Audrey.
Vince and Dave go to North Carolina to find out more from Dave's secret past but searching may cause a new trouble back in Haven; people are switching bodies.