‘Vivien was barking mad from the word go,’ Laurence Olivier reflected in later life, and Lyndsy Spence’s biography would fully concur with the summing-up. At best, the actress was ‘suspended in a dream world’, unable to separate herself from the classic characters she played – Scarlett O’Hara, with her dark hair and flashing eyes, or Blanche DuBois (‘she is a tragic figure and I understand her’).