This is part of a series of thrillers featuring the agent Tweed and his associates. These reflect the international political and diplomatic concerns of the era. A vast banking concern called INCUBUS is expanding its influence into Eastern bloc nations, including Russia. When it is learned that this concern may be using rather idiosyncratic methods of intrusion, for instance terrorism and blackmail, Britain's best SIS agents Tweed, Paula Grey and Bob Newman are sent to investigate. An entertaining, with well-described Scandinavian locales and an original story idea, and thrilling plot make this thriller well worth reading.