A poster advertising the 1927 film Metropolis, the world's first full-length science fiction movie, has been sold for a record £390,000.
American art impresario Ken Schachter bought the art deco image from the Reel Poster Gallery in Notting Hill.
The price far eclipsed the previous record for a movie advert: £252,000 paid for a poster from 1932's The Mummy, which was sold at Sotheby's in New York in 1997.
The Metropolis poster's previous owner was Andrew Cohen, chairman of direct mailing company Betterware, who is thought to have a personal fortune of almost £150 million.
Directed by Fritz Lang, Metropolis took more than two years to complete. It is a stark, Orwellian look at life in the year 2000, when a workforce of slaves is ruled by robots and a small capitalist elite of humans.
The striking poster with images of towering city blocks was created by artist and graphic designer Heinz Schulz-Neudamm. The print sold to Mr Schachter and is one of only four surviving examples.
