(CNN) When Carlota Prado was asked to enter the "diary room" on the Spanish version of the "Big Brother" reality TV series, it would have seemed an entirely mundane request.

The room is central to the show's format, which sees a group of people living together in a house, watched at all times by television cameras. It's there that contestants hear directly from "Big Brother," gossip about their fellow housemates, and deliver messages to the outside world.

But Prado was called for a different reason. The previous night, after falling unconscious following an alcohol-fueled party put on for contestants, she was allegedly sexually abused by another contestant, José María López. López denies the allegations, his lawyer told Spanish media.

With no recollection of the 2017 incident, producers asked Prado to report to the diary room, where she was forced to watch the alleged abuse. Her distraught reaction was also captured.

The footage shows Prado bursting into tears and begging the Big Brother figure, known in Spain as Super, to stop playing the footage. She is heard to say: "Please stop, Super, please," complaining that her heart was beating quickly and asking for something to relax her.

The Super figure then asks Prado not to tell the other contestants about the incident.

Neither the footage of the alleged abuse nor the diary room footage was aired at the time, but two years on, both were obtained by Spanish news network El Confidencial following an investigation by the site.

Since then, the show's handling of the situation has sparked a scandal in the country. The network behind the series has apologized for its response, but scores of major companies have nonetheless pulled advertising from the show.

The episode is particularly painful in a nation that has seen a number of deeply divisive sexual assault cases in recent years. At the heart of this incident is Spain's controversial law, which specifies that non-consensual sex in which violence or intimidation is not used is charged as sexual abuse, and not the more serious charge of rape.

Protesters carry a banner through Madrid reading 'We are the wolf pack. It not abuse, it is rape" during a demonstration in 2018.

The same law was thrown under heavy scrutiny following the Wolf Pack case , which brought thousands of protesters onto the streets and prompted anger at the Spanish judicial system.

Meanwhile, some critics have demanded the cancellation of "Gran Hermano," and asked whether reality television -- an industry never far from provoking anger -- has ever stooped so low.

'This is a human being'

The incident began when the show's overnight crew became aware of the suspected assault and informed more senior producers. Prado and López had been in a relationship on the show.

After the diary room scene, the production company said Prado was temporarily taken off the show to receive psychological support and López was removed from the show. Producers also referred the incident to police. Prado did not initially press charges, but has subsequently made a complaint which is being investigated by a Spanish court.

López's lawyer, Antonio Madrid, told El Confidencial his client was trying to help Prado while she was drunk, and denied any allegations of wrongdoing. CNN has been unable to contact Madrid.

Endemol Shine, the UK-based production company behind the "Big Brother" franchise, told CNN: "We'd like to stress no footage was ever shot with the intention of being broadcast. However, with hindsight we regret that the conversation where Carlota was informed took place in the diary room environment," where contestants interact with the Big Brother character.

"The footage was only supplied as evidence when requested by the authorities, encrypted and guarded," the company added. "The decision not to inform the housemates of the incident, and why Carlota was asked not to mention the incident at the time, was taken by the production team in good faith at that point, in order to protect her privacy and because the incident was due to be reported to the police." CNN has been unable to reach Prado's lawyers.

But Honey Langcaster-James, a chartered psychologist and director of services at the organization On Set Welfare , said she had grave concerns about the way the incident was handled.

"This isn't just a TV show contestant, this is a human being," she told CNN. "There are a number of members of the production crew able to watch what's going on in the diary room, either from the gallery or on set. That isn't a controlled environment."

Reality television faces a reckoning

Langcaster-James has worked as a consultant psychologist on the UK version of "Big Brother," one of the world's most successful reality television formats. She said there is "usually a facility to get somebody away from the set and away from the cameras -- if somebody receives bad news from home, for example."

But she said the incident shines a light on a problem reality TV is still grappling with. "One of the problems with the reality TV industry at the moment is that it is down to the individual production companies to make a judgment as to what kind of on set welfare they need to be putting in place."

"The problem with that is that people who aren't trained in mental health or wellbeing are making decisions about what kind of safeguards need to be put in place."

Several incidents in the UK have drawn attention to the way in which reality contestants' welfare is handled. The deaths of two former "Love Island" contestants and the suicide of a guest on "The Jeremy Kyle Show" in particular have prompted calls for a review.

And last month, two Dutch reality shows -- "The Villa" and "Temptation Island" -- were canceled over controversial scenes featuring interactions between the male and female contestants.

Zeppelin, the unit of Endemol Shine that produced the Spanish series, added that it would review its protocols. "Gran Hermano" is currently airing its seventh celebrity season, and has aired 18 regular seasons since its launch in 2000.

The environment in which this alleged incident took place is unique, but the anger that underpins much of the conversation in Spain is painfully familiar in the wake of the so-called Wolf Pack scandal, in which five men were charged with sexual abuse but not rape. Following more than a year of protests across the country, the men eventually had their convictions upgraded

Spanish bank BBVA is among the companies to have pulled advertising from the show.

Sensitivities were strong enough that numerous major companies, including BBVA, Nissan and GlaxoSmithKline, dumped the show once the scandal erupted.

And Langcaster-James believes that reckoning could be good news for the industry.

"The TV industry is a very unique setting," she said. "We have seen a shake-up of this industry in recent years, and I think that is a positive step.

"Whenever something like this happens, it brings it into public consciousness, and challenges us to think again about what welfare provisions are put in place."