With the ending of the Second World War, Lief Bangsboll, after distinguished service with the O.S.S. behind enemy lines in Denmark, prepared himself for a life of peace and hopefully love with the young Canadian girl he had met while training at Camp X during the war. But the United States War Department and the Office of Strategic Services had other plans for the young soldier/agent.

In September 1945, Lieutenant Bangsboll was secretly sent into Soviet-occupied Germany to assess and report upon Russian military activities in and around Berlin. In December 1945, a deadly incident occurred in which a KGB agent was killed, and Leif and his O.S.S. team were forced to escape back into the American sector of Germany. With his O.S.S. identity compromised and himself now target of the KGB, Lieutenant Bangsboll was re-assigned to the regular U.S. Army and became a member of the 82nd Airborne Division at Fort Bragg. With the outbreak of the Korean War, Leif was part of the first airborne operation in which he and the 187th Airborne Regiment Combat Team parachuted into North Korea as part of the US/United Nations force confronting the North Korean invasion.

During his year of combat in Korea, Captain Bangsboll, the platoon leader for the Headquarters Intelligence & Reconnaissance platoon, worked under Lieutenant Colonel Aaron Bank, also a former OSS agent. During that assignment Leif led numerous special operations missions behind enemy lines, including a mission to recover a large cache of American gold bullion which had been left behind when the U.S. 8th Army was overrun during a North Korean offensive. He also led a secret parachute mission to rescue American /United Nations' prisoners of war held in North Korea and a daring assault on a North Korean base which earned him the Silver Star for 'extraordinary courage in combat'.

Captain Bangsboll played a crucial role in the develop of the United States' first Special Forces unit and was appointed as one of the initial Company Commander of a Green Beret/Special Forces unit. Then, as the Army Liaison Officer to the 302nd Tactical Reconnaissance Wing in Sembach, West Germany, he flew as an observer, reporting on Soviet troop movements over Warsaw Pact held territory and instructed American pilots the skills of escape and evasion. As a Company Commander with the 10th Special Forces Group in Ulm, West Germany, he stood his ground, facing Soviet and East German combat troops poised to invade Western Europe during the tense days during the U2 spy plane incident and the Cuban Missile Crisis.