Marks & Co, also incorrectly referred to as "Marks & Company" or colloquially as "84", was a well-known antiquarian bookseller located at Cambridge Circus - 84, Charing Cross Road, London. The shop was founded in the 1920s by Benjamin Marks and Mark Cohen. Cohen was persuaded to allow his name to be abbreviated in the company's name. It provided the basis for the book of correspondence by Helene Hanff entitled 84 Charing Cross Road, later made into a stage play, television play and BAFTA-winning film. The shop has since been knocked through into 24 Cambridge Circus, and the premises were converted for restaurant usage. A plaque on the wall commemorates the shop and the book. In May 2015, the premises was opened as a McDonald's. The sign remains on the front of 84's original building.