Jean Fleury

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.

Pierre can no longer pay for his medical studies and disappears for several months. During his absence, his fiancée allows herself to be courted by a reveler. Back home, Pierre cannot regain the trust of the young woman, who now leads a dissolute life of which she is ashamed. She tries to kill herself. Pierre saves her and heals her.

Hopson, a prestigious scientist, studies the effect of snake venom to cure many diseases of mankind. His son enlists in the army when the Great War breaks out. A series of circumstances will lead the scientist to change his way of thinking about values ​​and principles that until then he had as immovable.