Welcome to Eris an island with one house, one resident and one road leading out. Connected to mainland Scotland by a narrow strip of land, Eris is inaccessible for twelve hours a day when the tide comes in. The island was once home to Vanessa Chapman, a renowned artist whose notorious adulterous husband disappeared twenty years ago. Now, the artist's sole heir, Grace Haswell, lives there in isolation. But when a stunning discovery is made at a London art gallery, an unexpected visitor disrupts Grace's solitude. So the secrets of Eris may be revealed...