When white, bourgeoise married couple Loretta and Henri have difficulties running their bistro, called Le Ventre Plein (The Full Belly), 18-year-old black orphan Diamantine is hired on as a waitress. Assuring Diamantine that she's now one of the family, the couple convince her to assist them in a ruse by pretending she's pregnant. Taking this for a joke, Diamantine soon discovers the real cause for this charade.