Juan Pérez is a waiter in a luxurious place where the bachelor party of a man who is going to get married for convenience is done. When a dancer and singer with whom he was entangled, chases him, he uses Perez to get rid of her.
In an all-girls boarding school, one of the students resists the will of her uncles to marry her off because she does not know her future husband. Which is why she pretends to be a prude for whom marriage is a dirty word.
Détectives inséparables et séduisantes, Mari et Lola, surnommées les « Lèvres Rouges », se transforment en justicières pour aider la police, dirigée par le commissaire Fernandez, à se débarrasser la ville des criminels.