Cynthia Hall, 24, a former fashion model married millionaire George Stockton, 57, and found she was living in a gilded cage – spied upon by her jealous husband and the victim of poison pen letters. When George dies of poisoning Cynthia is arrested. Leading criminal lawyer Archer MacFarlane Bishop agrees to handle Cynthia’s defence and in doing so becomes besotted by her. At the expense of his personal life and the esteem of his friends, he pieces together a case for the defence.
When he discovers Cynthia has had an affair with her late husband’s nephew, Dick Marsden, he slants the defence to incriminate him. Cynthia is acquitted, but that is far from the end of the story.
Thirty Days Hath September features a guest appearance by Portia Manning (of Portia Faces Life fame) as Special Assisting Counsel.