MADRID: Roman Polanski`s political thriller "The Ghost Writer" picked up the critics` award for best picture as the San Sebastian film festival got underway here Friday.

Polanski "is an author in every sense" and "every aspect of this prize is his," said British actress Olivia Williams, who accepted the Fipresci Grand Prix 2010 award on behalf of the film.

The International Federation of Film Critics’ (FIPRESCI) 296 members worldwide selected the film, which also won Polanski the best director prize at the Berlinale in February, as the top movie of the year.

Based on Robert Harris`s bestseller "The Ghost", the film features a stand-out performance by Pierce Brosnan as a former British prime minister modelled on Tony Blair being probed for war crimes over the torture of terror suspects.

He hires a ghost writer (Ewan McGregor) to shape up his memoirs but the hired scribe soon stumbles upon a deadly web of transatlantic intrigue.

Polanski missed the world premiere of the film at the Berlinale as the 76-year-old director was under house arrest in Switzerland where he was fighting a US extradition request over a 1977 case of sex with a 13-year-old girl.

Switzerland rejected the request in July.

Eighteen films are in the official competition at the 58th edition of the San Sebastian film festival, which wraps up on September 25.

BDST: 0838 HRS, September 18, 2010