36th Perry Mason Mystery written in 1950. Openings of Mason Mysteries are always strange, but this book's opening is rather unusual. When Mason has a pleasant time at a night club, he receives a phone call from an anonymous woman who urgently asks his help for a seemingly not-so-urgent matter. Mason ordinarily tosses away such an anonymous request, but he is moved by the woman's frantic, horrified tone.
At last, Mason traces a highly likely woman, but she stubbornly denies that she called him. WHY? This riddle is the most interesting in this book. The answer doesn't fail my expectation. And the meaning of the "One-Eyed Witness" is not so simple such as the witness has a bad eyesight. That doesn't fail my expectation, either.