Metropolis is a monumental work. On its release in 1925, after sixteen months' filming, it was Germany's most expensive feature film, a canvas for director Fritz Lang's increasingly extravagant ambitions. Lang, inspired by the skyline of New York, created a whole new vision of cities. One of the greatest works of science fiction, the film also tells human stories about love and family. Thomas Elsaesser explores the cultural phenomenon of Metropolis: its different versions (there is no definitive one), its changing meanings, and its role as a database of twentieth-century imagery and ideologies. In his foreword to this special edition, published to celebrate the 20th anniversary of the BFI Film Classics series, Elsaesser discusses the impact of the 27 minutes of 'lost' footage discovered in Buenos Aires in 2008, and incorporated in a restored edition, which premiered in 2010.