Free-spirited and prone to fantasy, fifteen-year-old Tamsyn Tresize will never forgive herself for her father's death.

When Tamsyn meets Edie Davenport, the privileged daughter of wealthy Londoners, she is immediately drawn to her sophisticated manner and rebellious personality. The Davenports welcome Tamsyn in to their lives at the Cliff House, their stunning art deco home with a striking black-tiled swimming pool, which overlooks the brooding coastline not far from the ruined tin mines of Botallack.

Haunted by memories, dreams and vivid premonitions, Tamsyn seeks solace in her deepening friendship with Edie and the perfection of the Cliff House.

But nothing is ever perfect.

Though Edie relishes the companionship of Tamsyn, who looks up to her and makes her feel special, her attention soon shifts to Tamsyn's handsome, troubled brother, and the friendship begins to sour. As the summer draws to an end, tensions, jealousies and passions erupt, culminating in a shocking and terrible tragedy that will change their lives forever.