War time propaganda film starring Humphrey Bogart as Sergeant Joe Gunn who along with his tank crew picks up five British soldiers, a Frenchman and a Sudanese man with an Italian prisoner while crossing the Libyan Desert to rejoin their command after the fall of Tobruk. They arrive at a desert fortress desperately in need of water. A detachment of German soldiers arrive and attempt to barter for water but Gunn refuses and a fierce battle ensues.