Umberto Lenzi—who belongs on the Mount Rushmore of Italian horror stylists alongside Dario Argento, Mario Bava, and Antonio Margheriti—directed this 1980 horror actioner about a horde of radioactive mutants that attack a city. Though often referred to as a zombie movie, the film makes quite clear that these monsters are not walking dead but the result of nuclear testing. Lenzi uses this distinction to take anti-authoritarian swipes at mass media and militarism, but he also changed how zombies were depicted in movies; the infected masses of Nightmare City wield weapons and are quick on their feet, a far cry from the lurching creatures of the day.