La Marquesa (Libertad Lamarque) is a needy woman who lives in the street. She's always drunk, but she has a great voice and sings to pedestrians at nights in order to earn some money. One night, a famous singer, Pedro Vargas (himself), offers her the opportunity of making a live TV presentation. But La Marquesa is to drunk to see the importance of the offer and she simply rejects it. Next day, La Marquesa is put in jail because she breaks into a residence, trying to get a letter from her daughter. After spent some time in jail, along with other needy women, La Marquesa gets out from jail thanks to the kindness of a young man, who finds out that the woman is in fact an authentic marchioness, named Cristina Payarés. Time later, Cristina, now become a wealthy woman, lives in a residence and receives the visit of her daughter from Argentina with some news: she's going to get marry. It won't be easy for Cristina to accept her daughter's fiancé and things got complicated because the police ...