It is the winter of 1946, and after years of war, ex-Special Operations Executive agent Duncan Forrester is back at his Oxford college as a junior Ancient History Fellow. But his peace is shattered when a much-disliked Fellow is found dead in the quad, stabbed and pushed from an upper window. A don is suspected and arrested for the murder, but Forrester is not convinced of his friend's guilt. On the hunt for the true killer, he finds himself plunged into a mystery involving lost Viking sagas, Satanic rituals and wartime espionage.

Duncan Forrester's research on an Aegean island is interrupted first by the murder of a British archaeologist, and then by the outbreak of the Greek Civil War. The worship of ancient gods may provide a clue to the murderer, but in such a tumultuous time, little is what it seems.

It's 1947. As Britain's new Labour government struggles to cope with the break-up of Empire, there's a grisly murder in the British Museum, terrorists target British Foreign Secretary Ernest Bevin and Forrester boards the Queen Mary for a fateful voyage to New York.