An eleven-day luxury cruise through the Bahamas was supposed to be nothing more than sunburns, overpriced cocktails, and too many TikToks. For the Slytherin-adjacent friend group—Draco Malfoy, Mattheo Riddle, Pansy Parkinson, Blaise Zabini, Theo Nott, Daphne Greengrass, Astoria Greengrass, and her—it turns into something far messier.