Secrets of War: WWII’s Most Famous Undercover Operations

From a failed attempt to assassinate Adolf Hitler to a successful faking of British invasion plans, these are some of the boldest covert operations during World War II. Some of them were successful in changing the course of the war, while others failed miserably. World War II brought spy missions and espionage to levels the world had never seen before. (Also see our list of weapons from World War II that completely failed.)

To compile a list of famous top-secret missions of World War II, 24/7 Tempo consulted various sources, including the Jewish Virtual Library, the National World War II Museum, Espionage History Archive, Military History Now, History, Britannica, and War History Online. We exercised editorial discretion to select the missions that gained the most fame and in some cases impacted the outcome of the Second World War.

Here are famous undercover missions of World War II:

• Took place: 1939-1943
• Nations involved: Nazi Germany
• Outcome: The Nazis used a high-class Berlin brothel, Salon Kitty, to spy on clients

• Took place: 1940-1943
• Nations involved: Great Britain
• Outcome: The British used Jewish refugees from Germany to redirect German planes from attacking British targets

• Took place: 1941
• Nations involved: Great Britain
• Outcome: British commandos neutralized cargo ships in Fernando Po (now Bioko), the Spanish island off the coast of West Africa, that were believed to be fueling U-boats

• Took place: December 7, 1941
• Nations involved: Japanese Empire
• Outcome: The Japanese surprise attack on American ships at Pearl Harbor severely damaged the US fleet

• Took place: February 27, 1942
• Nations involved: Great Britain
• Outcome: Also known as the Bruneval Raid, British parachutists landed near Saint-Jouin-Bruneval in France to disassemble a coastal radar station

• Took place: April 18, 1942
• Nations involved: United States
• Outcome: Surprise attack on Tokyo boosted U.S. morale after Pearl Harbor attack

• Took place: May 27, 1942
• Nations involved: Czech resistance
• Outcome: Czech resistance assassinated Reinhard Heydrich, Reich Protector of Bohemia and Moravia

• Took place: June 1942
• Nations involved: Nazi Germany
• Outcome: German saboteurs picked up on Long Island for their plan to sabotage American infrastructure

• Took place: August 1942
• Nations involved: Great Britain/Canada
• Outcome: Amphibious attack on the German-occupied French port city of Dieppe that ended in disaster

• Took place: December 1942
• Nations involved: Great Britain
• Outcome: Kayak raiders attacked cargo ships in the German-occupied port of Bordeaux

• Took place: December 1942-1943
• Nations involved: Italy
• Outcome: The Italian cargo ship Olterra was stuck in Spain, anchored in the Bay of Gibraltar. Italy scuttled the Olterra to prevent capture by the British forces.

• Took place: Nov. 28-Dec. 1, 1943
• Nations involved: Nazi Germany
• Outcome: Nazis inserted assassins in Tehran, Iran, to assassinate Winston Churchill, Joseph Stalin, and Franklin Roosevelt at the Tehran Conference but they failed

• Took place: April 1943
• Nations involved: Great Britain
• Outcome: Fake Allied plans to invade Sardinia and Greece to divert Nazi Germany from the real invasion of Sicily

• Took place: April 18, 1943
• Nations involved: United States
• Outcome: U.S. warplanes intercepted a plane carrying Japanese admiral and Pearl Harbor attack architect Isoroku Yamamoto and downed the plane over Bougainville

• Took place: May 16-17, 1943
• Nations involved: Great Britain
• Outcome: British Lancaster bombers damaged two hydroelectric plants in Germany's Ruhr Valley. The mission was immortalized in the movie "The Dam Busters"

• Took place: Sept. 22, 1943
• Nations involved: Great Britain
• Outcome: Six British midget submarines, known as X-craft, damaged the German battleship Tirpitz in Norway

• Took place: Sept. 12, 1943
• Nations involved: Nazi Germany
• Outcome: German commandos rescued Italian dictator Benito Mussolini from Allied captors

• Took place: Feb. 27, 1943
• Nations involved: Great Britain/Norway
• Outcome: Norwegian commandos blew up a heavy water production site — material used to develop atomic bombs — setting back the German program

• Took place: 1943-June 1944
• Nations involved: Western Allies
• Outcome: A disinformation campaign designed to have Nazi Germany believe invasion could take place anywhere along the 1,500-mile coastline

• Took place: April 1944
• Nations involved: Great Britain/Crete
• Outcome: British commandos kidnapped General Heinrich Kreipe, the German commander of occupied Crete

• Took place: Spring 1944
• Nations involved: Nazi Germany
• Outcome: Adolf Hitler's espionage plan to kill Joseph Stalin, one of many plots under Operation Zeppelin, failed

• Took place: June 1944
• Nations involved: Western Allies
• Outcome: Creation of phantom armies designed to fool the Germans into thinking the Allies would land in France at the Pas de Calais instead of Normandy

• Took place: July 1944
• Nations involved: German resistance officers
• Outcome: Failed attempt to assassinate Adolf Hitler at Wolf's Lair headquarters in East Prussia

• Took place: December 1944
• Nations involved: Nazi Germany
• Outcome: A team of commandos dressed as British and American soldiers sowed chaos behind U.S. lines at the start of the Battle of the Bulge

• Took place: January 1945
• Nations involved: United States/Philippines
• Outcome: US rangers and Filipino guerrillas rescued 513 prisoners from the Cabanatuan prison of war camp

• Took place: March 1945
• Nations involved: Japanese Empire
• Outcome: Japan planned to crash planes carrying infectious fleas in the cities of San Diego, Los Angeles, and San Fransisco area. The plan was scrapped due to strong opposition from Chief of General Staff Yoshijirō Umezu