In Paris the young ex-paratrooper and would-be boxer Michel Maudet loses his first big fight and is sacked by his manager.

Needing a job, he answers an ad for a male secretary able to travel and is hired on the spot by Dieudonné Ferchaux, senior partner of a failing bank who has a criminal past.

Next morning, Ferchaux is able to collect millions of dollars from his safe-deposit box but cannot touch his US bank account because the French authorities are seeking his extradition.

Renting an isolated house in New Orleans, Ferchaux seems to fall sick and Maudet gets increasingly frustrated at the whims of an old man with no power left beyond his attaché case of dollars.

Going to the neighborhood bar for drink and company, Maudet mentions his boss's stash to the owner Jeff, a reputed crook and murderer, and then picks up a dancer Lou in a night club.

He dismissed the film as 'more than usually trashy Simenon turned into a would-be thriller, with Belmondo perpetuating his irresistible, smilingly evil, stereotyped self'.

[11] Magnet of Doom has been described as a "mood piece" where "Very little actually happens in the film, other than the ambience: seedy, squalid, aimless, listless, stirred by Michel’s discontent, boredom and sexual longing.

[8] At the Institut des hautes études cinématographiques in 1964, Melville lectured about the importance of set design and art direction using scenes from the film as demonstrations.

[14] The pilgrimage to Frank Sinatra's birthplace and the "hypnotic car rides" in the film are seen as the most emblematic of Melville's "mystical Americanophilia".