Fleeing the humiliating arrest of her husband-to-be on the eve of their wedding, Celia Kilbride, a gems and jewelry expert, hopes to escape from public attention by lecturing on a brand-new cruise ship, the Queen Charlotte. She meets Lady Emily Haywood, the owner of a priceless-- and cursed-- emerald necklace that she intends to leave to the Smithsonian after the cruise. Three days out to sea Lady Em is found dead-- and the necklace is missing. As the list of suspects grows Celia, with the help of her new friends Willy and Alvirah Meehan, sets out to find the killer.