The former Rolling Stones star Brian Jones died after drowning in his swimming pool at the age of 27 - just two days before his ex-band members were to put on the concert of a lifetime at London's Hyde Park. Jones had already been axed from the group, despite co-founding it, after his drug and alcohol dependence caused concern, and his history of drug possession meant he struggled to get a touring visa for the USA. 

The Stones decided to persevere with the concert, scheduled for July 5 1969, but the respectful tribute they'd planned ended in disaster. Mick Jagger was to read a sombre poem by Percy Bysshe Shelley, to be timed with the release of thousands of white butterflies, which would flutter symbolically across the stage. However, the plan was fraught with struggles right from the beginning, as gig promoter Andrew King shudderingly recalled. 

"I had to liaise with this butterfly farm in the West Country and the park's people were very concerned the wrong sort of butterflies might upset the ecosystem of the park,” he recalled.

After much negotiation, they agreed to the stunt, only for King to peek inside the boxes he'd been given and find nothing but "dead" insects.

"I called the butterfly farm in a panic and said, ‘They’re dead!’" he told Uncut magazine, "and they said 'They’re not dead, they’re cold, they are sleeping, you’ve got to warm them up.'”

With just minutes to spare, the panicked promoter found himself scrabbling around backstage looking for hot plates to warm the unresponsive insects up.

He recalled in horror that they looked like "the sort of thing students use to warm up baked beans”.

The first disaster took place when one of the boxes caught fire, inches away from where the Stones were performing at the time.

Then the second mortifying incident culminated in the prized butterflies either flying or dying - not quite the moment Jagger had hoped for as he read the poem.

"When Mick opened the boxes, some of them flew away, but most dropped senseless on the stage,” King cringed.

"[Those ones] weren’t dead, they were cold. They only died when they got trod on.”