As people prepare to evacuate the island, one wedding guest mysteriously disappears. Several of the wedding party reluctantly volunteer to stay behind and search the island, but the situation changes when Abby receives a distressing phone call. Sheriff Mills continues his search for the killer, but finds himself in a dangerous game of cat and mouse.

Madison reveals who is responsible for her disappearance, leaving the remaining guests stunned and confused. When an attempt to flee the island in Jimmy's boat results in disaster, the group are forced to take refuge at The Cannery.