Trivia

Genevieve Waite had been Michael Sarne's girlfriend, but their relationship was over by the time they made this film together.

This was the first feature film to be directed by Michael Sarne. It got mostly very bad reviews in Britain, where its release was delayed until 1969. Then, it was shown in the lower half of a double-bill with "Pretty Poison" to an indifferent box-office response. However, in America, where it had been screened earlier, it had a modest financial success, which led Twentieth Century Fox to make the catastrophic decision to entrust Sarne with the direction of "Myra Breckinridge", one of the biggest disasters (and most reviled films) in the studio's history. Gore Vidal, the original author of "Myra Breckinridge", had seen "Joanna" and called it one of the worst films ever made, making it unlikely that any film made from his novel by the same director would be anything but terrible.

Tony Hatch and Jackie Trent were asked to write the theme song. However it was dropped in favour of Rod McKuen's music, but went on to be a major UK hit for Scott Walker

A novel adaptation of the story was written by Michael Sarne.

Michael Sarne originally wanted his then-girlfriend Gabriella Licudi for the title role.