Christine Keeler
At the height of the Cold War, she became sexually involved with a married government minister, John Profumo, as well as a Soviet diplomat.  A shooting incident between two of her other lovers caused the press to investigate her, revealing that her affairs could be threatening national security. In the House of Commons, Profumo denied any improper conduct but later admitted that he had lied. This incident discredited the Conservative government of Harold Macmillan in 1963 in what became known as the Profumo affair.