Guy Foucher (Nino Castelnuovo), a 20-year-old French auto mechanic, has fallen in love with 17-year-old Geneviève Emery (Catherine Deneuve: Belle de Jour), an employee in her widowed mother’s chic but financially embattled umbrella shop. On the evening before Guy is to leave for a two-year tour of combat in Algeria, the pair share a passionate night. Geneviève becomes pregnant and then must choose between waiting for Guy’s return or accepting an attractive offer of marriage from a wealthy diamond merchant (Marc Michel).