Dominic Salt and his three children are caretakers of Shearwater, a tiny island not far from Antarctica. Home to the world’s largest seed bank, Shearwater was once full of researchers, but with sea levels rising, the Salts are now its final inhabitants. Until, during the worst storm the island has ever seen, a woman mysteriously washes ashore. As they nurse Rowan back to strength, it begins to feel like she might be just what they need. Rowan starts imagining a future where she could belong to someone again. But she isn’t telling the whole truth about why she set out for Shearwater. And when she discovers sabotaged radios and a freshly dug grave, she realizes that Dominic is keeping his own secrets. As the storms on Shearwater gather force, they all must decide if they can trust each other enough to protect the precious seeds in their care before it’s too late.

Franny Stone has always been the kind of woman who is able to love but unable to stay. Leaving behind everything but her research gear, she arrives in Greenland with a singular purpose: to follow the last Arctic terns in the world on what might be their final migration to Antarctica. Franny talks her way onto a fishing boat, and she and the crew set sail, traveling ever further from shore and safety. But as Franny’s history begins to unspool --- a passionate love affair, an absent family, a devastating crime --- it becomes clear that she is chasing more than just the birds. When Franny's dark secrets catch up with her, how much is she willing to risk for one more chance at redemption?