Murders headline Boston tabloids in 1908, and Inspector Brody knows the prime motives are revenge and jealousy. The slaying of singing star Rosetta Rice seems no exception, and his chief suspect is a disgruntled vaudevillian lodging at Portridge Arms, a theatrical boardinghouse run by the Porridge Sisters (so called for their vegetarian cuisine). Florrie and Lavinia, however, believe Rosetta's murder was an unintended consequence of machinations by theatrical robber barons. Murder at the Tremont Theatre is an historically accurate mystery peopled with a cast of eccentrics.