I'm surprised the release of this movie in America in the 90s compelled some viewers to reconsider Varda's stature as a feminist director.
Seems clear to me she was presenting an ironic picture of happiness right off the top, with the colorful spring flowers and the impossibly-in-love couple, set to Mozart.
Then the husband starts making faces at the telegraph girl even though his wife has given him no reason to wander. He tries to justify this lack of fidelity as ''love for two women" and of course the mistress buys it. But there's no way the viewer is buying it.
Eventually he gets around to telling his wife, but he's not quite as up-front with her as he was with the mistress. But listen to the musical cues. The happy Mozart that has repeated for the first 65 minutes is gone. Replaced by foreboding Mozart.
Meanwhile, watch how the wife builds the kids a bona fide sleeping lean-to to keep them safe from park critters while they sleep.
Husband tries to spin his self-justifying nonsense with an analogy. She seems doubtful, but he appears to win her over and they make love, then fall asleep.
After the tragedy he barely misses a beat before taking up with the mistress again. She's introduced to the kids and they go for a walk in the autumn park setting, now with a Mozart fugue. She tells them, ''I'll build you a house'' and she puts three little sticks together that is basically a 1/25-size version of the protective structure the actual wife had built for them early that summer.
She's a fake, in other words. A pretender. An interloper. A pale copy.
And what does the husband do? ''I'm going for a walk.'' He's already day-dreaming about wandering off from the mistress/fake-mom.
Sure, Varda doesn't spell it out and have characters yell at each other. Or paint him explicitly as a devil. But that's the point. The husband comes in a pleasant, slick, good-looking, superficially loving package.
He's a fraud. The mistress is a fraud. They wear matching sunflower yellow cardigans in the final scene, an autumn tone of yellow to mimic the bright spring yellows he and the real wife were rolling around in during the spring park scene.
This movie is pure poetry and Varda is a genius.