When Unity, Connecticut's Independence Day cannon firing ends in disaster, historian Christian Shaw finds herself in the middle of a murder case-and a land-use dispute involving a possible Revolutionary War battlefield. Worse, her new client is hanging around the Historical Society looking for ideas for a Regency romance reality show. And then she gets involved with 90-something Amy Taylor's bat mitzvah. Now, Christian, her new man, Assistant State's Attorney Joe Poli, son Henry, who has a photographic memory and Type-1 Diabetes, and the colorful cast track the killer through artifacts, land records-and the annual zucchini glut-culminating in a wild and dangerous scene on Amy's big day.