Finally released from gaol, Will Crosby, quits England for a new life in Queensland, hoping to regain self-confidence, and the lost esteem of his former wife, Alice. However, his hopes are soon dashed when a typhus epidemic breaks out on board The Emigrant which is then re-directed to the ill-prepared quarantine station on Stradbroke Island.
Tom Brown, disgraced former Home Secretary, is missing presumed dead. The police had been seeking him in connection with the deaths of several people, and his disappearance affectively closes the case.
In the 1970s computers were just beginning to have an influence on the Secret Services.Quickly, too much information was coming into G.C.H.Q and things were being missed The Collation Unit was set up underground in six floors beneath some old hangars at Mannington airfield just outside Cheltenham to make connections and prioritise everything.