Ben struggles with the siren's song effects, but Ryn also struggles with her feelings for him and Maddie, too.
Ben's struggling with Ryn's siren song, as she also struggles to hold onto power amongst her people.
Ben struggles with the siren's song. Xander finds out about the merpeople on land.
More of Ryn's people come to the shores. But something's forcing them there.
Helen reveals more of her history. Bristol Cove deals with the aftermath of a merfolk attack.
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.
Decker shows up in Bristol Cove, which causes all sorts of damage.
Ben works with his Ted, to find info from the inside. Maddie gets to know Elaine better. Chris returns to Bristol Cove.
The longer Ryn is out of the water, the more she deteriorates. At the military compound, the other mermaid causes chaos.
Maddie and Ben try to help Ryn, as well as study her. Xander tracks down a lead on Chris, who's still locked up in the military's lab.