The orphan Catherine Maguet, nicknamed "La grande Maguet", was taken in by a young and good chatelaine, Suzanne de Norvaisis. Edmond, the husband of the latter, during a trip abroad, falls madly in love with another and will go, to conquer this one, to poison his wife. Imprisoned then released, the lord will finally marry the one for whom he has become a criminal. But the great Maguet will avenge her beloved murdered benefactress...
In France during World War I, Marthe waits for her husband, Jacques, while he fights on the front lines. Marthe then begins a tempestuous affair with 17-year-old François, with whom she had a dalliance before marrying Jacques. Jealous François struggles with the fact that Marthe is married, while she tries to prove her devotion to her young, hotheaded lover. Things become even more complex when Marthe becomes pregnant with Jacques' baby.