Pedro Quijano is a cattle tender who used to be the champion in milk production and lowest mortality of cattle in a site of Escambray mountains in Cuba. For this reason he was normally called Pedro Zero Percentage. Pedro had a family composed of two daughters, Carolina who used to work always with his father, and Purita quiet rebel lovesick in Lupesio, the son of Vicente, another cattle tender, but Pedro's enemy. Their rivalry consisted in their competition to be the most productive cow producer of the region. Vicente had once one of his cows dead and for this reason he was called Vicente Menos (Minus One). The other Vicente's daughter, Blanquita, was lovesick of the Pedro's god son, Trino. So with all this enmity, the couples were never allowed to meet. The end of the film showed a reconciliation of both families for the health of cattle production in that area. Reynaldo Miravalles and Orlando Casin acted very well and gave the necessary colour to this comedy.