Picture this scenario: you walk into a room filled with a bunch of naked people. You're all about to voluntarily have sex.
But one of them has an incurable sexually-transmitted infection. You don't know who that person is.
And you're strictly not allowed to use a condom.
Makes for a crazy story, right?
Over the past week, reports have emerged of this supposed rising new trend called "Sex Roulette" parties.
The story has been making the rounds since it first appeared on the Spanish news site El Periodico, entitled: "Swingers in Barcelona have a secret AIDS patient as a guest in the orgy".
The Daily Mail's lengthy headline reads: "Sex roulette parties where one person is secretly HIV+ and nobody is allowed to use condoms are on the rise, warn doctors."
The Mirror reports: "The risky orgies offer the 'thrill' of not knowing whether or not you will be infected - which medics say shows people have 'lost respect' for HIV."
But the problem with these reports is a lack of evidence. In fact, despite their using the plural "doctors", all the outlets quote just one source - Dr Josep Mallolas from Hospital Clinic Barcelona - who specialises in HIV prevention.
He told el Periodico that this trend is a sign that people have "lost respect" for the severity of HIV, because it can now be treated.
Subsequent reporting has been contradictory. The Daily Mail claims these "thrilling" parties are conducted exclusively by gay men. Others, like the Parent Herald, have reported it's the latest trend among teenagers.
Sole source Dr Mallolas was asked to clarify his comments and provide evidence to news.com.au of the parties he described taking place.
"In the last two or three years, and in several large western cities like London, Paris and now Barcelona, there is a clear evidence of such 'parties' called Chemsex," he told news.com.au in response.
"Chemsex is a concept where several people, mainly men who have sex with men, are in a place and they used a lot of drugs like mephedrone and methamphetamine for a long sexual party.
"It is in this kind of party where the people lose their control and they do things otherwise they never would do."
But the "Chemsex" trend, while it does exist, is a separate issue with nothing to do with these reports.
Chemsex parties are basically orgies fuelled by hook-up apps, in which participants take illegal drugs such as crystal meth and GHB before having sex for lengthy periods of time.
While dangerous and disturbing in their own right, their existence is hardly a revelation. The term "Chemsex" gained prominence in the mainstream media last year, after Vice released an unflinching documentary on the lives of various ongoing and former participants.
This is an ongoing issue, which has been described as the "biggest crisis in the gay community" since the Aids epidemic 30 years ago.
But "Chemsex" parties are in no way the same as the "Sex Roulette" parties reported in the media now. In fact, by conflating the two, Dr Mallolas may as well be admitting the latter is not really a thing.
When asked how big the purported phenomenon is, he said: "I really don't know."
The CEO of ACON, Nicolas Parkhill, told news.com.au: "The work of ACON, as a leading HIV and sexual health promotion organisation, is embedded within the gay community and we have never encountered the practice of 'Sex Roulette' parties happening here in NSW, or indeed, Australia.
"Overwhelmingly, gay men, both positive and negative, take the necessary steps to protect themselves and their partners from HIV transmission."
In a 2007 report, David Moskowitz explained that there's a clear, misunderstood difference between unprotected sex (typically the case in the world of "Chemsex") and a deliberate, active desire to catch, or flirt with the idea of catching HIV (as suggested in these "Sex Roulette" reports).
The latter actually does have its own term, called "Bugchasing", which refers to an obscure fetish in which an HIV-negative person seeks to become HIV-positive. This dates back to the 1980s.
As opposed to a "rising trend", however, bugchasing is largely considered an isolated fetish among a small minority of individuals.
"In reviewing the scarce unpublished and published materials on bugchasing, as well as general healthcare speculations, a common theme appears - the lumping of bug chasers with barebackers," writes Moskowitz.
"Although these two groups share some of the same practices, namely unprotected anal intercourse (UAI), there are distinctions that differentiate bugchasing... even though all bugchasers are indeed barebackers, not all barebackers are bugchasers."
In other words, there's a difference between intending to catch HIV, and having unprotected sex where HIV acquiral is a risk.
For comparison's sake, you could consider people who don't necessarily want to get pregnant, but have unprotected sex regardless.
New York City University sociologist Christian Grov believes it's an "overblown" topic. He told Broadly: "Look, for every fetish that's out there, you can find someone who's into it.
"If you want to find someone with one leg who wants to dress up in a clown costume and have a threesome with you and a rubber duck, you can find this person in the world. So certainly these parties are real and possible. But is it a thing? Probably not."
Gay news outlet Queerty described the initial reports as "a sorry attempt to drum up some good old-fashioned gay panic (and plenty of clicks.)"
Far from a "rising trend", we can probably assume this one is a hoax.