Oleg Vladimirovich Penkovsky, codenamed "Agent Hero" (Russian: Олег Владимирович Пеньковский; April 23, 1919, Vladikavkaz, North Ossetia, Soviet Russia, – May 16, 1963, Soviet Union), was a colonel with Soviet military intelligence (GRU) in the late 1950s and early 1960s who informed the United Kingdom and the United States about the Soviet Union placing missiles on Cuba, which led to the Cuban Missile Crisis.
Penkovsky's father died fighting as an officer in the White Army in the Russian Civil War. Oleg graduated from the Kiev Artillery Academy in the rank of lieutenant in 1939. After taking part in the Winter War against Finland and in the World War II, he had reached the rank of lieutenant-colonel.
A GRU officer, Penkovsky was appointed military attaché in Ankara, Turkey in 1955. He later worked at the Soviet Committee for Scientific Research. Penkovsky was a personal friend of GRU head Ivan Serov and Soviet marshal Sergei Varentsov 
Penkovsky approached American students on the Moskvoretsky Bridge in Moscow in July 1960 and gave them a package, which was delivered to the Central Intelligence Agency. CIA officers delayed in contacting him because they believed they were under constant surveillance. Penkovsky eventually persuaded the British spy Greville Wynne to arrange a meeting with two American and two British intelligence officers during a visit to London in 1961. Wynne became one of his couriers. The CIA regretted their earlier mistake, but were included by the British and they shared future information.
For the following eighteen months Penkovsky supplied a tremendous amount of information to his British Secret Intelligence Service handlers in Moscow, Ruari and Janet Chisholm, and to CIA and SIS contacts during his permitted trips abroad. Most significantly, he was responsible for arming President John F. Kennedy with the information that the Soviet nuclear arsenal was much smaller than previously thought, that the Soviet fueling systems were not fully operational, and that the Soviet guidance systems were not yet functional.
Soviet leadership started the deployment of nuclear missiles in the belief that Washington would not detect the Cuban missile sites until it was too late to do anything about them. Penkovsky provided plans and descriptions of the nuclear rocket launch sites on Cuba. Only this information allowed the west to identify the missile sites from the low-resolution pictures provided by US U-2 spy planes.
Penkovsky's activities were revealed by Jack Dunlap, a double-agent working for the KGB. The KGB swiftly drew the conclusion that there was a mole in their ranks and set about uncovering him. Penkovsky was arrested on 22 October 1962 - before Kennedy's address to the nation revealing that U-2 spyplane photographs had confirmed intelligence reports and that the Soviets were installing medium-range nuclear missiles on the Caribbean island - code named Operation Anadyr (see Cuban Missile Crisis). Thus President Kennedy was deprived of a potentially important intelligence agent that might have lessened the tension during the ensuing 13-day stand-off; intelligence such as the fact that Khrushchev was already looking for ways to defuse the situation.. Such information, arguably, would have reduced the pressure on Kennedy to launch an invasion of the island - an action which, it is now known, would have led to the use of Luna class tactical nuclear weapons against US troops. The Soviet commander, General Issa A. Pliyev, commander in charge, had been given permission to use these weapons without consulting Moscow first.
Penkovsky was tried and convicted of treason and espionage in a trial in 1963. As to his fate after conviction, accounts differ. Some sources allege that Penkovsky was executed by the traditional Soviet method of a bullet to the back of the neck and cremated. GRU agent Vladimir Rezun, known for his controversial books produced under the pseudonym "Viktor Suvorov" following his defection from the Soviet Union, alleges in his book Aquarium to have been shown a black and white GRU film where Penkovsky is shown bound to a board with a piano wire and 'cremated alive'. This graphic account has him slowly fed into a furnace alive, feet first, as other officers are made to watch, in a warning to potential traitors. A very similar description was later included in Ernest Volkman's popular book "Spies: The Secret Agents Who Changed the Course of History" .
The spying career of Oleg Penkovsky was the subject of Episode 1 of the BBC series "Nuclear Secrets", entitled "The Spy from Moscow". The programme featured original covert KGB footage showing Penkovsky photographing classified information and meeting with Janet Chisholm. It was broadcast on January 15, 2007.
Penkovsky is also mentioned in two of Tom Clancy's Jack Ryan books: The Hunt for Red October and The Cardinal of the Kremlin. In the Ryanverse, he is described as the agent who recruited Colonel Mikhail Filitov as a CIA agent (code-name CARDINAL), and in fact had urged Filitov to betray him in order to solidify his position as the West's top spy in the Soviet hierarchy. The supposed "cremated alive" story also appears in several Clancy novels, but is attributed to another agent named Popov (in the novel Red Rabbit).
Also mentioned in the book : "The Deceiver", by Frederick Forsyth, Bantam Books, 1992 ISBN 0-553-29742-2, p.43, 4th line.