Keira Knightley chose her ''bum double'' with the late Tony Scott.

The 26-year-old actress worked with the director - who committed suicide in August at the age of 68 - on action film 'Domino' in 2005, and the 'Anna Karenina' star remembers him being an ''extraordinary man''.

The most vivid memory she has of shooting 'Domino' - in which she played bounty hunter Domino Harvey - is of her and Tony casting their eyes over six naked butts to replace her own on screen.

She recalled: ''One day we stood in a room together, with six naked women, choosing me a bum double. We disagreed on whose bum was the best but, being a gentlemen, he gave me my way.''

Despite only working together for three months, Keira feels she was privileged to have crossed paths in her career with the 'Top Gun' filmmaker - the brother of Ridley Scott.

She told The Observer newspaper: ''The world is a lesser place without Tony Scott. He was an original in every way. There will never be another like him. He was the only truly rock 'n' roll person I've ever met. Watch his films, be part of his violent delights. He was, is, and always will be a legend.''