Strange tides are acting upon Dr Cass Bainbridge, impelling her to leave London and the comfortable home she shares with her lover, to take up a lecturing job on the south coast.
Yet Brighton isn't the natural choice for a woman with a long-standing fear of the sea. And some of the students on her course are anything but easy. Dealing with the mounting pressure of her new job is almost too much for Cass to handle and, beneath the surface, a whispering stream of disquiet is gradually building into a wave. For Cass is being stalked - a series of strange phone calls and disturbing emails, and a malignant presence around the flat, are forcing her to finally come to terms both with her own history, and the demons threatening her future.