A jewelry store is ransacked, leaving two policemen dead. A mysterious house is razed to the ground and the charred bodies of two terrorists are found. A ring of Russian anarchists have succeeded in spreading unease throughout Edwardian London, forcing the top men from the Home Office and the Police to pool their resources. Luke Pagan, young, ambitious and Russian-speaking, is the police officer co-opted into the newly formed MO5 together with his street-wise and somewhat unorthodox partner Joe Narrabone. Their brief is to observe three leading Russian revolutionaries who are wanted by the Ochrana, the Tsar's dreaded secret police. Casimir Treschau, Molacoff Weil and Janis Silistreau are involved in political activity up to the hilt, but only proof that their dealings are also criminal will enable the authorities to put a stop to the campaign of terror they are fostering.

A former London police officer turned special intelligence agent for the M.O.5., Luke Pagan enters his newest case chasing down a German spy, who is discovered traveling through and around Britain on the eve of the Second World War.

The slaughter of World War I in the trenches continues unabated. Luke Pagan finds himself in the Intelligence Corps, investigating an illegal organisation controlled by a Belgian, which is encouraging British soldiers to desert and move across to the German side. What began as a trickle now threatens to develop into a flood in the fourth year of war. Pagan enters dangerous territory and faces disaster.