Beyond a smoking-hot leading lady and a portfolio of car crashes and explosions, a good soundtrack is often what truly grants a film pop-culture immortality. Would Janet Leigh’s murder in Psycho have been quite as dramatic without Bernard Herrmann’s ominous, screaming strings? Would Darth Vader have seemed as formidable without John Williams’s pounding "Imperial Death March"? And would countless beach holidays have gone way, way better if it weren’t for Jaws’s nerve-shredding theme? It’s hard to imagine a contemporary film without some kind of musical accompaniment, but before the age of the studio orchestra (and the phonograph), movies were strangely disconnected from their soundtrack. A case in point is Fritz Lang’s silent sci-fi epic Metropolis; at the time of its premiere the film was accompanied by symphonic music that mish-mashed themes from Richard Wagner’s operas, among other late-romantic references. Since then it has been rescored on multiple occasions, and today we select and dissect our favorite reworkings.

The archetypal Italo disco producer, Moroder is the man who got many teens (and queens) bobbing their heads in 1977 with his fine work on Donna Summer’s out-of-this-world disco classic “I Feel Love.” He also wrote the theme for the welding/dance spectacular Flashdance. Moroder’s unexpected soundtrack for Metropolis featured his own euphoric synth compositions alongside a carefully selected group of pop songs from the likes of Bonnie Tyler, Freddie Mercury and Adam Ant. The glitzy pop-ness of it all tends to trample Fritz Lang’s weighty social allegory, but hey, it’s a good karaoke medley.  

Mills’s love for the collision of the old and modern world is clear: though he’s known as one of the pioneers of Detroit techno, in the course of his career he’s composed new music for Buster Keaton’s silent films, installations dedicated to Stanley Kubrick’s 2001: A Space Odyssey and performed some of his dance floor classics live with the Montpellier Philharmonic Orchestra. Created for a performance at Paris’s Centre Pompidou, his version of Metropolis brought ghostly, high-pitched synths and a bit of oontz oontz to Lang’s bustling future city. 

Best known for his stirring Golden Globe-nominated score for Tom Ford’s A Single Man, Korzeniowski has the most film-world cred out of all those that have approached Lang’s masterpiece. With a 90-piece orchestra, a choir of 60 and two vocal soloists, Korzeniowski’s moody, dark score is subtitled “A Symphony of Fear,” and was first played alongside a projection of the film at Poland’s Era Nowe Horyzonty film festival to great praise.

In just five years The New Pollutants’ evocative rescoring of Metropolis has achieved a lot: a rapturous premiere at the Adelaide Film Festival, a successful season at Melbourne’s Next Wave Festival, and this year, a performance at Pritzker Prize-winning architect Jørn Utzon’s Sydney Opera House. The Australian electronica duo (comprised of Benjamin Speed and Tyson Hopprich) created a soundscape bristling with thudding electronic drum beats and glitchy samples—an evocative contemporary take on the pounding pistons of the colossal factory that constitutes the underworld of Metropolis. The group is currently updating the composition for a performance at the Adelaide Film Festival in early 2011.