Juana Dayanara Barraza Samperio (born 27 December 1957)[1] is a Mexican serial killer and former professional wrestler dubbed La Mataviejitas (Sp.

[12] Barraza's mother, Justa Samperio, was an alcoholic who reportedly exchanged her for three beers to a man who repeatedly raped her in his care, and by whom she became pregnant with a son.

Investigating officers suspected that the killer posed as a government official, offering victims the chance to sign up for welfare programs.

An odd coincidence also distracted the investigation: at least three of Barraza's victims owned a print of an eighteenth-century painting by French artist Jean-Baptiste Greuze, Boy in a Red Waistcoat.

Soon after setting an investigation in motion, the police incurred further criticism by launching what one journalist described as a "ham-fisted" and unproductive swoop on Mexico City's transvestite prostitutes.

[11] By November 2005, the Mexican authorities were reporting witness statements to the effect that the killer wore women's clothing to gain access to the victim's apartments.

[citation needed] A major breakthrough in the case occurred on 25 January 2006, when a suspect was arrested fleeing from the home of the serial killer's latest victim, Ana María de los Reyes Alfaro, who lived in the Venustiano Carranza borough of Mexico City.

[18][13] To the surprise of many Mexicans, who had supposed the killer to be male, the suspect detained was Juana Barraza, 48, a female wrestler known professionally as The Silent Lady.

[13] Barraza closely resembled a model of the killer's features, which showed La Mataviejitas with close-cropped hair dyed blonde and a facial mole, and was carrying a stethoscope, pension forms, and a card identifying her as a social worker when she was detained.

[30] Some sources gave the film mixed reviews, with Decider saying it "offers the best and worst of the true-crime-doc genre" and is "occasionally lascivious", having "some fat to be trimmed", and ultimately saying it "too frequently reeks of crass exploitation" and recommending its readers to "skip it".

[30] However, Rolling Stone said the film "transcends its subgenre" and "walks a fine line between observing the serious and pointing out the ridiculous", and concluding that it "may be the year's best true crime doc".