A stubborn siren, a stranded selkie, and a deal to save the sea...

Sidra Solei is a cynical, deep-sea siren whose heart hardened after the final battle between her pod and the humans. When her sister arrives in the one place Sidra finds solace to inform her their pod's hunger has become too great, Sidra is determined to act.

Dead set on saving her starving pod, Sidra sets off beyond their territory for the first time since childhood. In the vast, open sea, she crosses paths with a pesky seal intent on stealing her catch. But when they're both caught in the same fisherman's net, Sidra discovers the seal is actually a selkie named Breena—the mortal enemy of the sirens.

Hungry and weary from their journeys, Sidra and Breena reluctantly join forces to avoid detection and stowaway on the fishing boat, headed for land.

Just as Breena and Sidra think they are in the clear, Breena's pelt is stolen. Unable to return to the sea without it, the two enemies strike a deal: Sidra will stay on land until Breena finds her pelt, and the two sea fae will fight against the mysterious force depleting their home of its fish.

During their time on land, Breena begins to thaw Sidra's icy heart, reminding her of who she was before the war, but will it be enough to overcome the violent history between sirens and selkies? Or will they return to their homes and forget the love blossoming between them?