The 22-year-old man was filming the stunt on Wednesday for video sharing site YouTube, where prank-based channels can boast tens of millions of subscribers.
It took five members of the West Midlands Fire Service to get a YouTuber's head free from a microwave in a prank gone wrong.
They protected his head using a plastic bag inside the electrical appliance and then mixed seven bags of Polyfilla and poured it around his head.
Watch Commander Shaun Dakin, officer in charge of the West Midlands Fire Service crew who responded, said: "As amusing as this sounds, this young man could quite easily have suffocated or have been seriously injured".
It took a crew from the West Midlands Fire Service one hour to pull apart the microwave and remove the cement after they were called to a house in Fordhouses, Wolverhampton, reported the BBC. "But we had to be extremely careful with the screwdriver, working so closely to his head", he added.
"The oven was being used as a mould, and wasn't plugged in".
Unforch the deeply stupid YouTuber hasn't been named, with all the pictures released conveniently hiding his face (what with it being cemented into a microwave and all) so we can not give him the online roasting he so deserves.
"This was clearly a call-out which might have prevented us from helping someone else in genuine, accidental need", he said.
Earlier, in June, a man trapped in a cement hopper for more than two and a half hours was rescued at a manufacturing company at 300 block of Sullivan Road in Aurora, Colorado.
His co-workers present at the time of the incident tried for about half an hour to help the man get out but being unsuccessful in their bid, finally called 911 for help.
Dakin said that the service's technical rescue crew helped free the man's head from the oven after an hour.