La Vouivre (1989) on Netflix

Plot summary

Arsène Muselier returns to his village when the First World War ends. The only wound he carries is to his head, and it now and then brings on spells of delirium and fury. He meets again the villagers he left: his mother, the farmhand who raised him after his father died, and the girlfriend he had before the war. He hears the old tale of La Vouivre, a creature with a woman's body, living in the marsh among vipers, and it takes hold of him. One day he sees the strange woman himself, naked and alluring, and is enchanted at once. He cannot tell whether she is real or a shape made by his damaged mind.