Alphaville combines the genres of dystopian science fiction and film noir. Although set far in the future on another planet, there are no special effects or elaborate sets; instead, the film was shot in real locations in Paris, the night-time streets of the capital becoming the streets of Alphaville, while modernist glass and concrete buildings represent the city's interiors. In addition, the characters refer to twentieth century events; for example, the hero describes himself as a Guadalcanal veteran.
Expatriate American actor Eddie Constantine plays Lemmy Caution, a trenchcoat-wearing secret agent. Constantine had already played this role in dozens of previous films; the character was originally created by British pulp novelist Peter Cheyney. However, in Alphaville, director Jean-Luc Godard moves Caution away from his usual twentieth century setting, and places him in a futuristic sci-fi dystopia, the technocratic dictatorship of Alphaville.
Thanks to Wolfgang for the tip!