Louis Roman is a secondhand goods broker in the Lyon region of France. He provides assistance to people and acts as a private investigator in cases involving suspected relatives or clients.

Three French sisters have their lives interrupted and their relationship called into question when their father returns to visit 15 years after having abandoned them and their now-deceased mother. Each responds differently to his return according to how her character evolved from her relation with him and his unexpected departure. They eventually realize, though, that the somewhat elderly father is quickly losing his memory and his ability to function, and the youngest daughter's decision to accept him again while she can ends up permanently changing her family ties with her sisters.

Fred Bonnemaison, a driven and self-centered Parisian food writer has to return to his home town, Lyon, when his mother, a lively octogenarian, runs away to join a community of free-thinking widows.

Professor Wilcox, recognized for his research on magnetic phenomena, decides, in the company of his assistant and a famous adventurer, to fight the evil forces which are devastating the planet.