Du coup de foudre à l'échafaud, « Casque d'or » est une tragédie Belle Époque à la beauté mélancolique. L'histoire d'un amour impossible, marqué par le destin, que portent Signoret et Reggiani, inoubliables.

Claire (Bulle Ogier) returns to France following the death of her actress friend Agathe (Loleh Bellon). She attends an auction of her friend's possessions, provoking memories of the past. As her camera glides across the auction house bric-a-brac, Yanick Bellon mixes past, present and future to create a delicate piece of cinematic poetry. Set to the music of Georges Delerue.