Synopsis
In a rambling apartment, a middle-aged couple, Yvonne and Georges, live with their 22-year old son Michel and Yvonne's spinster sister Léonie ("tante Léo"), who has also been in love with Georges. Yvonne is a reclusive semi-invalid, dependent on her insulin treatment, and intensely possessive of her son (who returns her immoderate affection and calls her "Sophie"); Georges distractedly pursues his eccentric inventions; it is left to Léo to preserve such order as she can in their life and their apartment, which she describes as a "gypsy caravan" ("la roulotte"). When Michel announces that he is in love with a girl, Madeleine, whom he wishes to introduce to them, his parents are immediately hostile and seek to forbid the relationship, reducing Michel to despair. Georges realises that Madeleine is the same woman who has been his own mistress in recent months, and he confesses all to Léo, who devises a plan to extricate father and son by forcing Madeleine into silent surrender of them both.
The family visit Madeleine in her apartment where they are impressed by her modest and well-disciplined manner. Michel's initial joy at this apparent reconciliation turns to despair as Madeleine is blackmailed into rejecting him by Georges's secret threats. Yvonne consoles her son with satisfaction as they return home. Léo however is appalled by the cruelty and selfishness of what has been done and decides to support Madeleine.
The next day Léo persuades Georges, and then the more reluctant Yvonne, that the only way to rescue the inconsolable Michel is to allow him to marry Madeleine. Michel and Madeleine are joyfully reunited, but Yvonne is unnoticed as she slips away and takes an overdose of insulin. When the others realise what she has done, it is too late to save her. A new order is established in the "roulotte".
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