In April, 2015, 30-year-old Russian man, Valery Spiridonov, announced that he will become the subject of the first human head transplant ever performed, saying he would volunteer to have his head removed and installed on another person's body.

If this sounds like some kind of sick joke, we're right there with you, but unfortunately, this was - and still might be - all too real.

Earlier that year, Italian surgeon Sergio Canavero outlined the transplant technique he would intend to follow in the journal Surgical Neurology International, and said he planned to launch the project at the annual conference of the American Academy of Neurological and Orthopaedic Surgeons (AANOS) in the US in June, where he will invite other researchers to join him in his head transplant dream.

At the time, it sounded completely outlandish - and it still does today - but the difference was that Canavero actually found himself a living, breathing volunteer willing to be the guinea pig for what Christopher Hootan at The Independent predicted to be a 36-hour operation requiring the assistance of 150 doctors and nurses. You can read about the procedure here.

Hootan brought home what really would be at stake for Spiridonov - it's not just death he'd have to worry about:

"A Werdnig-Hoffman disease sufferer with rapidly declining health, Spiridonov is willing to take a punt on this very experimental surgery and you can't really blame him, but while he is prepared for the possibility that the body will reject his head and he will die, his fate could be considerably worse than death," says Hootan.

"I would not wish this on anyone," said Dr Hunt Batjer, president elect of the American Association for Neurological Surgeons. "I would not allow anyone to do it to me as there are a lot of things worse than death."

From speaking to several medical experts, Hootan pin-pointed a problem that even the most perfectly performed head transplant procedure could never mitigate - we have literally no idea what this will do to Spiridonov's mind.

There's no telling what the transplant - and all the new connections and foreign chemicals that his head and brain would have to suddenly deal with - might have done to Spiridonov's psyche, but as Hootan puts it rather chillingly, it "could result in a hitherto never experienced level and quality of insanity".

This could still actually be happening, and we're terrified.

Also, I've suddenly got a great idea for a movie, and judging from the creepy performance below, Canavero could pretty much be cast as himself:

A version of this story was originally published in 2015.

The last news on this intended head transplant was Canavero claiming late last year to have successfully transplanted the head on human cadaver.

Still creepy. Stay tuned.