Ryn must undergo a difficult process to ensure the survival of her species
Ben must put aside his jealousy in order for Ryn to mate.
Ryn takes Ben and Maddie to a secret place below the ocean. Levi returns to land.
Nicole helps Ben and Maddie research the siren song appropriately. Other discoveries come to light.
The merfolk have a civil war between their hierarchy on land, involving everybody in Bristol Cove.
Bristol Cove mourns, as Xander discovers the truth about Ryn.
Ben goes out to sea, trying to thwart the military. But there's worse trouble than the government on the water.