To uncover what really happened to her twin brother, one girl must dive into the freezing depths of the sea.
Since her twin brother, Eddie, drowned five years ago, sixteen-year-old Elsie Main has tried to remember what really happened that fateful day on the beach. One minute Eddie was there, and the next he was gone. Her father retreats into silence and her mother into tears, leaving Elsie alone with the gaps in her memory.
Seventeen-year-old Tay McKenzie is a cute and mysterious boy that Elsie meets in her favorite boathouse hangout. He is reckless and guarded, but he treats her like an ordinary girl instead of a tragedy.
When Tay introduces Elsie to the world of freediving, she vows to find the answers she seeks at the bottom of the sea. Deep in the freezing coastal waters, she searches the seabed for the memories she lost.
