The Story Behind Keira Knightley's Emerald Green Slip Dress From 'Atonement' Vogue She walked into the room, and time held its breath. Keira Knightley's emerald silk in Atonement (2007) wasn't just a costumeit was cinematic seduction. Named the best movie dress of all Keira Knightley Green Dress Etsy Atonement keira hi res stock photography and images Page 2 Alamy The green dress which Keira Knightley wore in Atonement (2007) has been named the best of all time by InStyle Magazine. Exceeding some classics as Audrey Hepburn's little black dress in Breakfast