Call it the mother of all science-fiction movies, and you won’t be far off the mark.

To view Metropolis, Fritz Lang’s deliriously extravagant 1927 allegory of dehumanized masses and applied cybernetics, is to marvel at its profound influence on later generations of filmmakers (and their production designers). The crowning achievement of German silent cinema, it has survived and thrived as the visual and thematic template for hundreds, maybe thousands, of films, comic books, teleplays — and MTV clips. No kidding: When Madonna immersed herself in “Express Yourself,” director David Fincher (Seven, Fight Club) filmed a music video for the 1989 pop song as an elaborate, ultra-glossy, sepia-toned homage to Lang’s sci-fi classic.

But wait, there’s more: Lang’s darkly grandiose vision of a time-warped dystopia — a teeming, sprawling cityscape where retrograde fashions and artifacts are juxtaposed with futuristic technology, mountainous skyscrapers and soulless Modernism run amok — also has inspired other contemporary visionaries as diverse as Tim Burton (Batman), Terry Gilliam (Brazil), Luc Besson (The Fifth Element) and Steven Spielberg (Minority Report).

Remarkably, none of the aforementioned acolytes who directed under the influence of Metropolis had ever seen Lang’s film in its entirety before making those cited films. Indeed, even the justly praised 2001 restoration of Metropolis, which incorporated footage from archives throughout the world, was not the Metropolis viewed by audiences during its brief theatrical run in Berlin and Nuremberg more than three-quarters of a century ago.

It was not until 2008 that what has been described as “an essentially complete copy” of the 1927 masterwork fortuitously was discovered by a Buenos Aires museum curator. The Museum of Fine Arts, Houston, is one of only a handful of United States venues that will get to screen a newly struck print including long-lost footage from that copy before the “complete” Metropolis is released on home video.

The film is slated for a five-performance run, Thursday through Monday, at the Museum of Fine Arts' Houston Brown Auditorium (with shows at 7 p.m. Thursday, Friday and Saturday; 5 p.m. Sunday and 2 p.m. Monday). Meaning that, come the morning after Labor Day, several hundred venturesome H-Town cineastes will be counted among the fortunate few ever to have seen Metropolis the way Lang intended it to be seen.

So be forewarned: If you are not in that number, you will have denied yourself the rare opportunity to savor on the big screen a unique and electrifying extravaganza, an ambitiously conceived and audaciously executed epic charged with alternating currents of cautionary fabulosity, Expressionistic imagery, kitschy melodrama, pseudo-religiosity and anything-goes razzamatazz.

Scripted by Thea von Harbou, Lang’s wife at the time of the film’s production, this seminal sci-fi spectacle pivots on escalating tensions between the pampered oligarchy that rules the futuristic city of Metropolis from atop immense skyscrapers — and the downtrodden workforce that toils far, far below the city streets. Lang’s theatrical background is reflected in his memorable (and much-imitated) depiction of shift changes, as solid blocks of workers, heads bowed, devoid of distinguishing characteristics, march into and out of elevators, forming symmetrical arrangements like those employed by legendary stage director Max Reinhardt.

The broad silent-movie performances on display throughout the film are frequently amusing, especially when displays of wanton lust are called for. But many of the main characters – especially Rotwang (played by Rudolph Klein-Rogge), a gleefully mad scientist with an artificial hand (shades of Dr. Strangelove) and the most dangerous fembot this side of an Austin Powers misadventure — are so indelibly vivid, they long ago evolved into archetypes.

Freder (Gustave Frohlich), the ever-so-sensitive son of Metropolis ruler Joh Fredersen (Alfred Abel), falls madly in love with Maria (Brigitte Helm), a spiritual advisor for the exploited workers, and follows her below the surface, where he witness a horrific industrial accident. (During one of film’s many feverish fantasies, Freder imagines the workers as human sacrifices, marching into the maw of the great god Moloch.) But Fredersen doesn’t want his son hanging with the wrong crowd. And he doesn’t want Maria stirring up the masses. So he asks Rotwang to transform the fembot into a faux Maria, to instigate unrest that he can quell with an iron fist.

Not surprisingly, nothing good comes of this.

What does it all signify? Well, what do you want it to signify? In 1927, German leftists were quick to condemn Metropolis as implicitly fascistic; at the same time, the right attacked the film as Communist rabble-rousing. Even now, Lang’s masterwork remains one of the provocative Rorschach tests ever conceived for the cinema: You can read almost any motive or meaning into its action and imagery.

Which is not to say, however, there is no method to the apparent madness. In truth, there is an underlying foundation of mirror images and counterbalances throughout Metropolis. The brave new world according to Fritz Lang is a place where ancient religious imagery (both Christian and pagan) can be glimpsed amid the high-tech futurism, where totalitarian control of the overworked masses is disrupted by the equally dangerous dynamic of anarchy and mob violence.

While the dehumanized workers are transformed into automations, Rotwang seeks to replace a lost love — who left him years earlier to marry Joh — with his “feminine” robot. As critic A.O. Scott has noted, Metropolis “stands between Frankenstein and (Steven Spielberg’s) A.I. as an expression of the defining modern preoccupation with machines that blur the boundary between the human and the mechanical.”

For decades, unfortunately, audiences have had access to only bits and pieces of Lang’s magnum opus. In an ironic foreshadowing of what happened decades later to Ridley Scott’s Blade Runner (1982) — which was drastically altered, and outfitted with voiceover narration, after disastrous preview screenings — Metropolis was withdrawn from release shortly after its 1927 premiere at a length of roughly two and a half hours, and whittled down to a more audience-friendly length.

More cutting was mandated by Paramount, the film’s U.S. distributor, which hired dramatist Channing Pollock to write new English title cards and, while he was at it, rearrange scenes to suit his own narrative designs. So many other versions were cut-and-pasted that Lang eventually resigned himself to the permanent loss of his original epic. When asked about Metropolis during his sunset years, he usually would reply: “Why are you so interested in a film that no longer exists?”

In the early ’80s, movie music composer Giorgio Moroder (Flashdance, Midnight Express) devoted $2 million to restoring much of Metropolis. When he was finished, however, he switched on his synthesizer, hired some rock vocalists — including Pat Benatar and Freddie Mercury — and prepared a soundtrack that turned the reconstituted classic into something that looked and sounded like … like … well, like the oldest and longest music video in the MTV playlist.

Trouble is, until the 2001 restoration, anyone who wished to savor Metropolis had to settle for the Moroder folly. Either that, or endure the incomprehensibly incomplete public-domain versions available only in scratchy 16mm prints (or muddy-looking VHS and DVD editions).

It speaks volumes about the bravura genius of Lang’s visual stratagems and hyperbolic melodrama that, even in bastardized and/or borderline-unwatchable forms, Metropolis managed to inspire so many major (and minor) filmmakers, and establish itself so firmly in our collective pop-culture consciousness. Most classics merely are immortal. But Metropolis has proven to be indestructible as well.

And now, at long last, its story once again is complete — with a happy ending.

The new trailer for the classic: