Eloisa is an orphan, the fiancée of Agustín, who meets her when she arrives in Madrid fleeing her stepmother's mistreatment. She happens to be the mother of an illegitimate child, but in reality the mother is his cousin Irene (with whom he lives, next to his aunt) married to Mr. Adrian. Her aunt Marcelina tries with this lie to save her daughter Irene. After numerous family entanglements, the truth becomes clear and the couple can live together and in peace.

All men who fall in love with Marichu die violently.