Advertisement Article continues below this ad MI5 Director General Ken McCallum ... Spies,” whose members spilled secrets to the Soviet Union from the heart of the U.K. intelligence establishment.

A briefcase abandoned by infamous Cambridge spy Guy Burgess as he fled to Moscow in 1951 is among the never-before-seen MI5 artefacts going ... being a Soviet agent. The note mentions how the ...

a 110-year-old lemon used for invisible ink and a letter about the Queen's response to news of a Soviet agent in Buckingham Palace are among MI5 artefacts on display in a "groundbreaking" new ...

MI5 Director General Ken McCallum told journalists ... “Cambridge Spies,” whose members spilled secrets to the Soviet Union from the heart of the U.K. intelligence establishment.