At a meeting they discuss visiting other planets, and almost everyone is reluctant to visit planet Earth, which hasn't been seen by any of them since the Napoleonic era: they see it as a very backward place, the most stupid people dominate the rest, the only use a tenth of their brain cells, it's full of pollution and still uses money, wages wars, believes women are inferior to men, has racists and other social inequalities. However, Mila knows that her mother was born there and would like to visit it. They wave her off as she flies away in a bubble.
She lands in the centre of Paris, but in a park. Venturing out she is horrified to see polluting cars and rubbish on the streets, and the unfriendliness of the people. She asks a shopkeeper something but she isn't understood, so she tries the different Earthly languages stored in her head until she finds French. She is given a sandwich to eat but it only makes her sick because it's basically junk food: she can only 'recharge' by holding a new-born baby, which she does by finding a maternity ward and caressing a baby until the head of department, Max (Vincent Lindon) threatens to call the police: she then uses a movement of her head to 'disconnect' Max, meaning that he transforms into a perfectly understanding, reasonable human being: all the way through the film, figures of authority are treated as ignorant villains whose essential job is to keep people down. In other words, this is a film with not only an egalitarian message, but a peaceful anarchistic one: we have all been brainwashed into believing the consumerist ethos that more means better, and in the process we have lost our humanity.
Obviously the film is not without its faults, and the (accidentally) disconnected orchestra scene and the (deliberately) disconnected football game (excellent though the latter is by deriding the stupidity of sport) go on for far too long. Having said that, this is a hugely original and inventive film. My only regret is that many viewers will just see it in terms of entertainment and not in terms of very strong social satire. This is not Les Visiteurs.