Worst fire since WWII
On 16 August 1980 John Thompson, a local petty criminal also known as ‘Punch’ and ‘The Gypsy’ got drunk at “The Spanish Rooms”, accused the barman, Jose Franco, of overcharging him and started a fight. He was kicked out of the club. Thompson returned shortly thereafter and poured petrol into the ground floor of the building and ignited it. 37 people died in the fire making it the worst fire in London in terms of loss of life since World War II. Thompson was imprisoned having been convicted of murder and died in prison in 2008 on the anniversary of the tragedy.
The Denmark Place was demolished in 2015 to make way for the redevelopment.
Read more about the tragic events of that night: https://robslondon.com/the-denmark-place-fire-1980/
Other sources: Wikipedia