Although several variations exist, the basic story tells of a beautiful woman by the name of Maria who drowns her children in order to be with the man that she loved. The man would not have her, which devastated her. She would not take no for an answer, so she drowned herself in a river in Mexico City. Challenged at the gates of Heaven as to the whereabouts of her children, she is not permitted to enter the afterlife until she has found them. Maria is forced to wander the Earth for all eternity, searching in vain for her drowned offspring, with her constant weeping giving her the name "La Llorona". She is trapped in between the living world and the spirit world. Parents often use this story to prevent their children from wandering out at night. Often it is said that if you lock the doors to a room with a mirror, light red candles and say her name a couple of times in front of the mirror, you may see her.

In some versions of this tale and legend, La Llorona will kidnap wandering children who resemble her missing children, or children who disobey their parents. People who claim to have seen her say she appears at night or in the late evenings from rivers or lakes in Mexico. Some believe that those who hear the wails of La Llorona are marked for death, She is said to cry, "¡Ay, mis hijos!" ("Oh, my children!").