El grano de mostaza.

Evelino Galindo, the serious owner of a porcelain store, argues with the womanizer jeweler Orcajo for an insignificant game of dominoes. Evelino, enraged, challenges him the next day to a duel in the gym. But after meditating a bit he starts to get scared. That is why, with the help of his friend Leoncio, he sharpens his wit to find a way to escape from combat. However, the situation is becoming more complicated.