Keira Knightley wears two different dresses in one at London Film Festival, we likey OK! Magazine A dress so iconic the original went missing! Keira Knightley's emerald silk gown in Atonement wasn't just the green dress it was the moment. Custom dyed, cut on the bias, and British Actress Keira Knightley arrives 04 September 2007 for the UK News Photo Getty Images Anyone else still thinking about Keira Knightley's backless green dress from Atonement, 13 years later? At the link in bio, our style editor examines why the backless trend became an unlikely Green Silk Satin Maxi Dress: Open Back Wedding, 'atonement' Style Etsy UK Atonement Cecilia Green Long Dress Backless Maxi Dress Keira Knightley Prom Dres eBay