How a 1940s Gangster Film Foresaw the Surveillance Tech of Today

White Heat is a classic gangster film from 1949, starring James Cagney. It is a thoroughly Los Angeles flick, filmed almost exclusively in the Greater Los Angeles region, including scenes shot at Warner Brother Studios in Burbank. The film is considered a classic for many reasons--but what's interesting specifically in terms of Gizmodo is its depiction of what, at the time, cutting-edge technologies that have been adapted by the police to track down Cagney's gang.