The owners of a country inn don't make their money by giving guests a place to sleep -- they earn it by killing them! So when a stagecoach makes a stop for the night, it offers a potential windfall to murderous innkeepers Pierre (Francoise Rosay) and Marie (Marie-Claire Olivia). Luckily, a traveling monk (Fernandel) learns of their diabolical plan in the confessional. But he'll have to come up with a brilliant scheme of his own to warn others without breaking his religious vows.