Tom Mangold, who presents the series, told Britain's Sunday Telegraph newspaper that Jagger fell out with the Hells Angels after a member of the notorious gang killed a fan during the band's infamous free concert at Altamont in 1969.
The Stones had hired the local chapter to provide security for the poorly planned concert near San Francisco. The bikers terrorized the crowd, and were offended by Jagger's effeminate dancing. One of them stabbed 18-year-old Meredith Hunter to death in front of the stage. The chaos was immortalized in the documentary "Gimme Shelter."

The Hells Angels felt they had been duped by Jagger as fingers were pointed in the aftermath of the concert. Former special agent Mark Young, who was interviewed for the BBC series, said a boatload of Hells Angels set out to take revenge on Jagger at his holiday home in the Hamptons, near New York City.

"The Hells Angels were so angered by Jagger's treatment of them that they decided to kill him," Mangold told the newspaper.
"They planned the attack from the sea so they could enter his property from the garden and avoid security at the front. The boat was hit by a storm and all of the men were thrown overboard. All survived and there was not said to have been any further attempt on Jagger's life."
Alan Passaro was arrested and tried for Hunter's murder in 1972 but was acquitted after a jury concluded that he had acted in self-defense because Hunter was carrying a handgun. Passaro later drowned in an accident.