Tells the inspiring story of The First Special Service Force, a secret Allied commando unit during WWII. They were also known as the Black Devils, the name given them by their terrified German enemy. They were the first combined U.S. & Canadian combat unit and were the forefathers of today's Special Forces. They never lost a battle or gave up an inch of ground and had the highest casualty rate of the war. The film explores their historic origins, brutal training for a secret mission, and legendary battle experiences through interviews with the veterans and descendants, archival footage and on location shooting in Montana, where they trained, and Italy and France.