The Count De Rochambeau wants to marry Mireille but she likes Etienne. The sister of Etienne, nicknamed "the girl with buttons" schemed with a friend to pose as a Russian princess to seduce the count and allow the marriage of his brother with Mireille.
Monsieur Charme is an old man, and the love of his life passed away some years ago. Despite being wealthy and in relatively good health, he finds that life without her is no longer supportable. Determined to end it all, he approaches Reine, a home-care nurse known for her willingness to bend the rules, and asks her if, in return for receiving his apartment, she will kill him. She readily agrees, and now the fun in this black comedy can begin. It seems that the old man has a nephew who is determined to thwart this scheme at all costs. A battle royal is joined between the ingenuity of the nurse and her willing victim, and the determination of his equally ingenious nephew.
