The widow Barny lives in Nazi-occupied France, looking after her half-Jewish daughter in a small village. When the Germans arrive, she decides to baptize her and chooses priest Léon Morin to do so. After spending some time with him, the relationship with her confessor turns into a confrontation with both God and her own repressed desire.
Melville avoids the implication that people who make unfortunate choices in wartime are intrinsically bad, or that support for the right cause automatically reflects essential goodness, confounding expectations by depicting a sympathetic German soldier and collaborationist, while picturing a GI who arrives with the liberating Allies as a boorish potential rapist. […] Melville shows us an extreme distortion of feelings produced by Barny’s loneliness and Morin’s immutable vow of chastity. Implicitly, the church and the war both impose a drastic curtailment of existential freedom; Melville is depicting a world where natural impulse and the choice it presents are preempted by contingency, transpersonal exchange weighted and warped by external circumstance.
— Gary Indiana (Criterion)
We perhaps anticipate Leon Morin, Priest will lead to sex. Melville is too good a filmmaker to settle for such a simple solution. To our astonishment, it leads to instruction in the Catholic faith.