Paula Grey and Bob Newman discover a woman's body floating on the Californian coast, her identity unknown. At the same time, a ship disappears into the fog. Sensing an impending catastrophe, Tweed hurtles across the globe, as a continent begins to slide into the ocean.

Colin Forbes was the principal pseudonym of British novelist Raymond Harold Sawkins (born in Hampstead, London on 14 July 1923, died on 23 August 2006). Sawkins wrote over 40 books, mostly as Colin Forbes. He was most famous for his long-running series of thriller novels in which the principal character is Tweed, Deputy Director of the Secret Intelligence Service.