The Death in the Drink - Viola Roberts Cozy Mysteries, #7

A local costuming guild has arrived in Astoria for a long weekend of recreating their favorite time period-the Regency. Think Jane Austen, sailing ships, high tea, a costume ball, and.a dead body. When the guild's nastiest member winds up dead in the drink, Viola is convinced it's no accident. And after the husband of the deceased gets into a brawl on the front lawn of the town's most well-known landmark, she knows something's up.
Armed with nothing more than a folding fan and her wits, she sets out to unveil the killer before somebody else winds up in Davy Jones's locker.