Millions of people around the world have watched a viral video that appears to show a woman taking direct action against "manspreading". So why do some think it is actually Kremlin-backed disinformation?
A woman creeps up to unsuspecting men on the St Petersburg Metro. The men are taking up lots of space, with their legs wide open. Before they can react, the woman dumps a bottle of diluted bleach onto their trousers. It's enough to make a stain, although not strong enough to cause serious injury.
The video was made by Anna Dovgalyuk, a Russian activist, student and social media star. And it racked up millions of views before being removed from YouTube.
The story was picked up by numerous news websites and caused a huge online uproar. Comments heaped praise, scorn, and more extreme threats of violence on Anna and others involved with the video.
But along with the video's viral spread came questions. Was it staged? And also was it - as some believe - a crafted piece of propaganda, sponsored and spread by the Russian government? And if it was, what was the aim?
Anna Dovgalyuk is relatively new to YouTube activism. The video was only her second post on the platform. Her first also had a feminist theme, and was also shot on the St Petersburg Metro. It was a protest against upskirting - taking photos up women's skirts - and showed a model (not Anna) lifting her dress to show passengers her underwear.
That video also got a lot of coverage, and prompted Anna to turn her attention to a project attacking "manspreading" - the phenomenon of men on public transport who sit with their legs wide open or otherwise inconvenience fellow passengers by taking up too much space.
"I thought that it was one of those problems which should be highlighted, that people should be made aware of," she told BBC Trending.
The video went up in late September, and was clocking up views at a rate of a million a day. But almost immediately, questions were raised about its authenticity.
An online news outlet in St Petersburg called Bumaga quoted a man who supposedly appeared in her video, admitting that he was paid to sit on the train and get squirted. Bumaga reproduced a post by the man on the Russian social network Vkontakte. (His account was deleted and the BBC could not immediately reach the man for comment).
Additionally, in the video, Anna states that it was created "in assistance with friends who share my position."
Speaking to the BBC, she denied that it was staged or that anyone was paid to get diluted bleach thrown on them.
"This is some completely random guy," she says, "I don't know what kind of actor he considers himself to be... but there is no evidence, it's just somebody's claim."
'Staged Kremlin propaganda'
The story took another turn when a European Union project to combat Russian misinformation, EUvsDisinfo, called the video "staged Russian propaganda".
According to this theory, the stunt was part of the Kremlin's surreptitious online interventions into various culture wars around the world, and designed to provide evidence that Western-style feminism has gone too far.
The EUvsDisinfo report gave the video another burst of publicity - and several of the same outlets which credulously reported on the video when it went viral ran reports with the European Union's take.
EUvsDisinfo cited two main pieces of evidence: the Bumaga report, and also the fact that the video was picked up and repackaged by a Kremlin-funded social media venture called In The NOW, which has more than three million likes on Facebook. In The NOW also has accounts on Twitter, Instagram, Snapchat and YouTube.
But In The NOW began as a TV programme on Russia Today - now known as RT.
RT and the news agency Sputnik, are directly funded by the Kremlin. Western governments as well as media critics have called them propaganda outlets.
And EUvsDisinfo sees the dark arts of the Kremlin at work in Anna's video and its treatment by In the NOW. "The video stages extreme feminist activism and manages to provoke extreme anti-feminist reactions," its post on the video concluded. EUvsDisinfo turned down a request for an interview about this story.
But is this a case of seeing Russian bogeymen where there are none? Wouldn't any social media company pick up on such clickable content?
In The NOW - which is based in Berlin - says that although it is financed by Russian government money, it has editorial independence.
"There's no top-down editorial memo that goes out, nothing like that," says J Ray Sparks, an American who is chief operating officer of Maffick, the German company that produces In The NOW. "It has never been some kind of propaganda outlet."
Although In The NOW doesn't deny that it receives money from the Russian government, this information isn't readily apparent on its Facebook page. When asked whether its mix of light-hearted stories and more serious news had ever included a video critical of Russian President Vladimir Putin, Sparks replied: "We haven't done anything recently."
In the NOW's video about Anna's manspreading stunt has racked up more than six million views.