Julia Bonatti wasn’t always a crime-solving San Francisco astrologer. She was a young woman, engaged to the love of her life, preparing for a teaching career when tragedy struck. Her fiancé was killed in a hit and run accident. As Julia struggles with her loss and attempts to find meaning in her life again, she takes refuge with her grandmother Gloria. But there’s little time for grief or rest because Gloria, a retired seamstress, needs Julia’s help. Gloria’s been hired to create costumes for a production of Agatha Christie’s Appointment with Death at the newly opened Theatre Mars in San Francisco’s North Beach neighborhood.

Theatre Mars is a stunning jewel, the cast is supremely talented and the script is brilliant. What could go wrong? Julia gets the first hint of trouble when her new friend, the owner of The Mystic Eye bookshop, warns that all might not go well. Opening night will take place during the dark of the moon, the last three days before the new moon, a time that bodes disaster for any new project. The dire prediction comes true when the lead actress is murdered before the final curtain, echoing the play itself. Julia discovers a vital clue to the murder, but a clue that puts Gloria’s life in grave danger. Can Julia rescue her grandmother before it’s too late? And will a black cat play a leading role?