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 ISABEL MARANT Etoile Women\'s Ro Linore Dress Green Khaki Outfits of Atonement: Keira Knightley wears Satin Green Dress to play Cecilia Tallis in the movie Spotern Isabel Marant Etoile Falone Dress in Green & Ecru FWRD Isabel Marant Louane Strapless Dress Blue Green Print Silk Viscose Blend Size 40