A young woman is forced to marry an old greedy man to save her father from bankruptcy although she has promised her heart to another man.

À l'été 1890, le curé Labelle pousse à la colonisation. Pour fuir Séraphin et la femme qu'il aimait, Donalda, Alexis s'est marié et établi sur une terre. Tous se liguent pour prendre leur revanche sur l'haïssable Séraphin.

Filmed in French, this Canadian film was based on a popular Quebec-based radio serial. The man of the title is miserable miser Seraphim (Hector Charland). Misanthropic to the point of insanity, Seraphim takes great pleasure in destroying the lives of everyone with whom he comes in contact. His current target is Alexis (Guy Provost), the ex-lover of Seraphim's long-suffering wife Donalda (Nicole Germain). Taking into consideration its daytime-drama source, it's understandable that Un Homme et Son Peche is plotted and paced like a soap opera. Star Hector Charland had previously spent 10 years portraying Seraphim on radio, so he's got plenty of "mean" at his disposal for this big-screen spin-off.