The moviemaker was stunned when an elderly stranger approached him at the U.S. premiere of the movie, based on the 1925 novel of the same name, and revealed she was the late writer's granddaughter.
He reveals, "Completely out of the blue a woman came out of the audience. She was quite old and frail. She held me by the hand and said, 'I've come to see what you did with my grandfather's book.'
"I went cold, because I didn't know it was Fitzgerald's granddaughter. She said, 'All his life he's been maligned because you can't transfer first-person narrative into film. In my opinion you have done it, and he would be very proud.'"
The granddaughter is believed to be Eleanor Lanahan, the granddaughter of Scott and Zelda Fitzgerald.