Even after the many books dealing with the Cambridge Five Burgess, Maclean, Blunt, Cairncross, and Philby it is still chilling to read of Guy Burgess's apparent offer to murder a Welsh academic who was capable of exposing him, or to contemplate the volume of secret material turned over to the Soviets.

ECONOMIST: History of espionage: Dark secrets | The

Hanssen, who was arrested in February, 2001, and was sentenced to life imprisonment in May, 2002, was not a rebel with a romantic attachment to Communism, like the British double agents Kim Philby, Guy Burgess, and Donald Maclean.

NEWYORKER: Double Lives