A struggling artist buys a talisman that gives him love, fame and wealth. The talisman is a severed left hand, and it works perfectly, in fact, magically. But of course there is nothing free in this world, and after one year the devil comes and asks for his due.

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.

During the latter part of World War I, Private Charles Plumpick is chosen to go into the French town of Marville and disconnect a bomb that the German army has planted. However, Charles is chased by some Germans and finds himself holed up at the local insane asylum, where the inmates are convinced that he is the "King of Hearts." Feeling obligated to help the inmates, Charles attempts to lead them out of town, but they are afraid to leave and frolic about the streets in gay costumes. Will Charles be able to deactivate the bomb in time and save his newfound friends?

1945 film by Marcel Carné