Jo Bergman, the Stones’ office manager, saw it too: 'On the day of the show there were these ugly people all around. Then I went into the tent with the Hells Angels. These people were very spooky.’ Hells Angels always scared me. I knew, of course, about their new peaceful reputation in the San Francisco scene. I’d read how Ken Kesey invited them to participate and how they would stand next to the stage at concerts in San Francisco, a kind of unofficial security presence.