Game Without Rules features Samuel Behrens and Daniel Calder, two secret British Intelligence operatives who work in the "E" (External) Branch of the Join Services Standing Intelligence Committee. Under the direction of Mr. Fortescue--a mild-mannered bank manager and secret spy-master--Behrens and Calder will sleuth, entrap, and, if necessary, assassinate whomever dares to threaten the peace of Britain and its inhabitants.

Whether they are investigating the identity of a dead officer in a secret bunker, infiltrating a dangerous circle of fellow spies, or rescuing a double agent, Behrens and Calder will keep the realm safe with precision, efficiency, and British camaraderie.