Life goes quietly in a traditional neighborhood of Madrid. Two beautiful girls, Susana and Casta, trade workers in the area, accepting mature attentions of a pharmacist, Don Hilarion. This affection dislike the young Julian, who is in love with Susan. Third movie version of the famous zarzuela by Tomas Breton. With musical arrangements by Gregorio Garcia Segura, the film tries to update the original story to fit the Madrid of the 60's.