She made John Lennon blush and Marlon Brando clam up. She cold-shouldered Princess Diana and humiliated Elizabeth Taylor. Jack Nicholson offered her cocaine and Pablo Picasso lusted over her. To her friends Princess Margaret was witty and regal, to her enemies, she was rude and demanding. Ma'am Darling looks at her from many angles, creating a kaleidoscopic biography, and a witty meditation on fame and art, snobbery and deference, bohemia and high society....