It's been described as a howl, a hum and a scream. But whatever you call the eerie sound emanating from Manchester's Beetham Tower, it seems to be annoying everyone who lives near it.
A clip taken on Sunday, when the city faced gale-force winds from Storm Clodagh, captured the eerie - and incredibly loud - noises made by the 47-floor tower on Deansgate every time the wind picked up.
And residents were quick to comment about the sci-fi sounds coming from the £150 million building:
And of course Twitter took the mysterious noise to a whole new level:
Architect Ian Simpson has apologised for the building's unintentional sound effects, telling the Manchester Evening News that they're caused by winds rushing over the glass "blade" at the top.
The blade is decorative, Simpson said.
"I am completely aware of the noise because I live at the top of the building," Simpson told the paper in 2012. "I would like to apologize for that and we are looking to address it so that next year we don’t have the same problem."
The 554ft-high Beetham Tower, completed in 2006, is the 12th tallest building in the UK and the tallest outside of London.