There are certain firearms that developed an almost iconic status during the 20th century, and the Thompson submachine gun, or "Tommy gun", is undoubtedly one of these. It had an unusual beginning, for it was developed during the dying days of World War I as a "one-man, hand-held machine gun" with the prototype referred to as the "Annihilator". The war ended before these first prototypes could be shipped to Europe but once the M1921 Thompson formally entered production it was enthusiastically used by the criminal fraternity working in Chicago and New York during the prohibition years of the 1920s. With the police increasingly outgunned, they too were forced to equip themselves with the Tommy gun. It soon became notorious as pitched battles were waged between gangsters and the police and through its use as an efficient execution tool in the infamous St. Valentine"s Day massacre. It quickly came to be used in Hollywood films and in the end its feature film appearances far outweighed its actual street use. By the end of the 1930s it would have probably faded from view had history not intervened. With the entry of the US into World War II there was an urgent need to equip and arm a force of epic proportions. Although the very concept of submachine guns had never been popular with the army, the Tommy was commercially available in quantity. As such, the Thompson submachine gun began a second career as part of the US Army. Moreover, it increasingly became the weapon of choice for the small band of British commandos as they conducted a number of daring raids against the heart of occupied Europe.