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 Satin V Neck Backless Jacquard Maxi Women 's Dress Elegant Evening Gown Hunter Green Lace Mermaid Prom Dress Graduation Dresses Long Backless Emerald Green US2 Sweetheart Sleeveless Backless Chiffon Green Prom Dress Custom Size Custom Color