We had sex in a Chinese hotel, then found out we had been broadcast in front of thousands of people.

One night in 2023, Eric was browsing a social media channel he regularly scans to find porn. A few seconds into a video, he froze.

He realized that the couple he was observing – entering the room, dropping off their bags and later, making love – was him and his girlfriend. Three weeks earlier, they had spent the night in a hotel in Shenzhen, southern China, without realizing they were not alone.

Their most intimate moments had been captured by a hidden camera in their hotel room and the images made available to thousands of strangers connected to the channel that Eric himself used to access pornography.

Eric (not his real name) was no longer just a consumer of the Chinese spycam porn industry, but a victim.

Warning: This story contains offensive language

So-called spycam porn has existed in China for at least a decade, despite the fact that the production and distribution of porn is illegal in the country.

But in recent years, the issue has become a regular topic of discussion on social media, with people – particularly women – exchanging tips on how to spot cameras as small as a pencil eraser. Some even set up tents inside hotel rooms to avoid being filmed.

Last April, new government regulations attempted to stem this epidemic, requiring hoteliers to regularly check for hidden cameras.

But the threat of being secretly filmed in the privacy of a hotel room has not gone away. The BBC World Service has discovered thousands of recent spy camera videos filmed in hotel rooms and sold as pornographic on several sites.

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Much of the material is announced on the messaging and social media app Telegram. In 18 months, I discovered six different websites and apps promoted on Telegram. Between them, they claimed to operate more than 180 spy cameras in hotel rooms that not only captured, but livestreamed, the activities of hotel guests.

I regularly monitored one of these websites for seven months and found content captured by 54 different cameras, about half of which were operational at any given time.

This means thousands of guests could have been filmed during this period, the BBC estimates, based on usual occupancy rates. Most of them are unlikely to know they were filmed.

Eric, from Hong Kong, began watching secretly filmed videos when he was a teenager, attracted by the “raw” nature of the footage.

“What attracted me was the fact that people don’t know that they are being filmed,” says Eric, now in his thirties. “I think mainstream porn seems very staged, very fake.”

But he experienced being at the other end of the supply chain when he discovered the video of him and his girlfriend “Emily” – and he no longer finds gratification in that content.

When he told Emily that their hotel stay had been filmed, edited into an hour-long clip and uploaded to Telegram, she thought he was joking. But then she saw the footage for herself and was mortified.

Emily was terrified that the clip might have been seen by her colleagues and family. The couple didn’t speak for weeks.

So how does this industry – which exploits the intimate sexual acts of unsuspecting couples for voyeuristic paying customers – work and who is behind it?

One of the most prominent spy cam porn traders I encountered was an agent known as “AKA.”

Posing as a consumer, I paid for access to one of the live streaming sites it was promoting – for a monthly fee of 450 yuan ($65, £47).

Once logged in, I had the option to choose between five different filming streams, each showing multiple hotel rooms – visible as soon as a guest triggered the power supply by inserting their access card. It was also possible to go back from the start of live broadcasts and download archived clips.

On Telegram – banned in China but commonly used for illicit activities – AKA advertised these live broadcasts. A Telegram channel had up to 10,000 members during our investigation.

Libraries of his live-edited clips are also available on Telegram for a flat rate. I was able to view over 6,000 videos in the archives, dating back to 2017.

AKA’s followers comment on Telegram’s channel feature, as they watch unsuspecting hotel guests – judging their appearance, gossiping about their conversations and rating their sexual performance.

They celebrate the moment a couple begins having sex and complain if they turn out the lights, thus shrouding them in darkness. Women are regularly described as “sluts,” “whores,” and “sluts.”

We managed to trace one of the spy cameras to a hotel room in Zhengzhou, central China, by piecing together several clues from followers, social media users and our own research.

Field researchers were able to gain access to the room and found the camera – lens pointed at the bed – hidden in the wall-mounted ventilation unit and plugged into the building’s power supply.

A hidden camera detector, widely sold online as a “must-have” for hotel guests, gave no warning that they were being spied on.

The team disabled the secret camera and the news quickly spread on Telegram.

“Zhonghua [name of the camera] has been removed!” wrote a subscriber on the main channel managed by AKA.

“It’s a shame, this room has the best sound quality!” AKA replied in the chat.

But complaints turned to celebration when, hours later, AKA announced that a replacement camera at another hotel had been activated.

“It’s the speed of… [our livestreaming platform]”, AKA told his followers. “Impressive, isn’t it?”

During our 18-month investigation, we identified a dozen agents as AKA.

Their interactions with subscribers made it clear that they were working for others higher up in the supply chain, whom they called “camera owners.” These people, the agents’ comments suggest, organized the installation of the spy camera and managed the live streaming platforms.

During our direct messaging with AKA, he accidentally shared a screenshot of a message from someone he said was a “camera owner”, with the profile name “Brother Chun”.

AKA quickly deleted the post and refused to discuss it, but we managed to contact “Brother Chun” directly. Despite our evidence that he provided the live streaming website to AKA, Brother Chun claimed that he was just another sales agent, even though he seemed to recognize that the supply chain extended beyond people like him.

What is clear is that there are significant sums of money to be made. Based on channel membership and subscription fees, the BBC estimates that AKA alone has earned at least 163,200 yuan ($22,000, £16,300) since last April. Last year, the average annual income in China was 43,377 yuan ($6,200, £4,600), according to the Chinese Bureau of Statistics.

There are strict rules on the sale and use of spy cameras in China, but we found it relatively easy to buy one at the country’s largest electronics market, Huaqiangbei.

It is more difficult to find precise figures on the number of people brought to court for spy camera pornography. Chinese authorities have shared far fewer details about legal cases in recent years, but the cases we found span across China, from Jilin province in the north to Guangdong in the far south.

Blue Li, of a Hong Kong-based NGO called RainLily – which helps victims remove explicit, secretly filmed images from the Internet – says demand is growing for her group’s services, but the task is proving more difficult.

Telegram never responds to requests to remove RainLily, she says, forcing them to contact group administrators – the very people who sell or share spycam porn – who have little incentive to respond.

“We believe that technology companies share a huge responsibility to solve these problems. Because these companies are not neutral platforms; their policies determine how content will be distributed,” Li said.

The BBC itself told Telegram, through its reporting function, that AKA and Brother Chun – and the groups they run – were sharing spycam porn through its platforms, but it has not responded or taken any action.

Contacted again 10 days later, with the full findings of the BBC investigation, Telegram told us: “Sharing non-consensual pornography is explicitly prohibited by Telegram’s terms of service” and “it proactively moderates…and accepts reports.” [of inappropriate content] to remove millions of harmful content every day. »

We officially reported our findings to Brother Chun and AKA that they were profiting from the exploitation of unsuspecting hotel guests. They did not respond, but a few hours later the Telegram accounts they used to advertise the content appeared to have been deleted. However, the website that AKA sold me access to still broadcasts live to hotel guests.

Eric and Emily remain traumatized by their experience. They always wear hats in public in case they are recognized and try to avoid staying in hotels. Eric no longer uses those Telegram channels to watch porn, he says, but he still checks them from time to time – terrified that the clip will resurface.

Additional reporting by Cate Brown, Bridget Wing and Mengyu Dong