It was later disclosed that she had assisted Fleming's counter-intelligence efforts during World War II.
She was responsible for helping deceive the Axis by creating a fictitious identity for a body that had turned up drowned in Operation Mincemeat.
The body was "disguise[d] as that of a naval officer, complete with totally convincing "secret" papers showing a different plan of attack ... [t]he body, appearing to be a casualty from a shot-down plane, would then be floated ashore in Spain, where local German spies would find it ... Fleming's task was to make the body totally convincing.
The book covers the minute attention paid to detail, which included placing theatre tickets and love letters in "Major Martin"'s pockets.
She was chairwoman of the Conservative MPs' Wives club for which she was appointed a DBE in 1991, ten years after her husband's knighthood.