Leo Zinser

Cops go under cover to track down a Mafia drug kingpin who has re-entered the country to sell "junk" to the prostitutes and "hopheads" on Bourbon Street. Edited from TV series N.O.P.D.

Made by RKO-Pathe, in Pathe color and three-dimension, in observance of the 150th anniversary of the Louisiana Purchase from France at a cost of $15,000,000 (more than the annual income of the U.S.A. at the time). After a short narrative showing U.S. Ambassador Robert Livingston (Val Winter) negotiating the purchase with Napoleon and Tallyrand, the rest of the film, guided by Livingston's spirit, visits the 1953 territory of the purchase and shows the growth of such former outposts as Minneapolis, Minnesota; Des Moines, Iowa; St. Louis, Missouri; Kansas City, Missouri and Kansas, and Little Rock, Arkansas. Most of the footage is given to New Orleans, Louisiana and its Vieux Carre, docks, business district and museums, ending with the preparation for that city's annual Mardi Gras.

Una noche, en los barrios bajos de Nueva Orleáns, el rufián Blackie y sus amigos matan a un inmigrante que les había ganado jugando al póker. A la mañana siguiente, el doctor Clint Reed del Servicio de Salud Pública confirma que el muerto tenía la peste negra. Para evitar una epidemia que tendría efectos catastróficos, Clint y el capitán de policía Tom Warren tratan de encontrar y aislar a los asesinos. La operación se lleva a cabo en secreto, por miedo a que la población sea presa del pánico. Disponen sólo de 48 horas para conseguirlo.