For fans and scholars of the silent-film era, the search for a copy of the original version of Fritz Lang’s “Metropolis” has become a sort of holy grail. One of the most celebrated movies in cinema history, “Metropolis” had not been viewed at its full length — roughly two and a half hours — since shortly after its premiere in Berlin in 1927, when it was withdrawn from circulation and about an hour of its footage was amputated and presumed destroyed.

But on Friday Film Forum in Manhattan will begin showing what is being billed as “The Complete Metropolis,” with a DVD scheduled to follow later this year, after screenings in theaters around the country. So an 80-year quest that ranged over three continents seems finally to be over, thanks in large part to the curiosity and perseverance of one man, an Argentine film archivist named Fernando Peña.

The newly found footage, about 25 minutes in length and first exhibited in February at the Berlin Film Festival, is grainy and thus easily distinguished from an earlier, partly restored version, released in 2001, into which it has been inserted. But for the first time, Lang’s vision of a technologically advanced, socially stratified urban dystopia, which has influenced contemporary films like “Blade Runner” and “Star Wars,” seems complete and comprehensible.