The art of the 'silent' pianist

My first inkling of the art demanded for the accompaniment of silent films came when I watched a young Carl Davis sit down at my piano and deliver a dazzling preview of his score for Abel Gance's five-hour epic, Napoleon. That was three decades ago, since when Davis's scores have become big business. Though his route has been orchestral, accompaniments on the piano are still provided for silent classics at the National Film Theatre. And the champion at that is the young classical pianist-composer Costas Fotopoulos, who has been providing the music for a clutch of rare Frank Capra movies at London's BFI Southbank, with the final one – Rain or Shine – due to be screened tomorrow.

"I try to treat my improvisations as organic compositions, rather than as extracts from a library of stock effects," Fotopoulos explains, adding that, at least when things go well, he follows the Wagnerian leitmotif tradition. He's never seen this film before: how does he deal with the challenge? "I fix on a strong leitmotif I can develop, and just concentrate on the moment and try to keep a sense of what may happen. I've learned to react very quickly to what I see, and I love the challenge." Having spent his life performing a wide range of classical composers, he's able to draw on a deep well of experience.

His wackiest exploit to date has been an improvisation to accompany a reading of one of Gordon Brown's laugh-a-minute budget speeches. Next up, George Osborne?

'Rain or Shine', BFI Southbank, London SE1 (www.bfi.org.uk; 020 7928 32 32), 6 & 16 November