The Pet Shop Boys will perform a soundtrack to the 1925 silent classic Battleship Potemkin in a free show in London, reports BBC News. The performance on September 12 will be part of a series of events taking place in Trafalgar Square. The group--out musicians Neil Tennant and Chris Lowe--said in a statement that the soundtrack would include three songs but would mainly be an instrumental score. German composer Torsten Rasch will orchestrate the score, which will be performed by the 16-piece Dresden Sinfoniker ensemble. Gay director Sergei Eisenstein's legendary film deals with a mutiny aboard a Russian battleship.