Nelly and Valle are at sailing school. For several days, they have learned to hoist sails and cruise across the bay. But there’s a spooky rumor going around: It is said that sometimes, a ghost ship can be seen rising from the dark waters. The old fisherman Enoch claims to have witnessed it with his very own eyes, even seeing a pirate step out onto the deck, hollering curses. It is said to be Captain Bluebeard, who ran aground in these waters in 1697! Valle, who is in line to receive training as a monster agent at the Monster Academy, can’t stop thinking about the captain. Why is he so angry? And why did he run aground when, according to Enoch, he was the most skilled sailor of his time? Even though there’s a competition at the sailing camp tomorrow, Valle just has to find out if this ghost story is true. He wakes Nelly and, in the moonlight, they sail out to Ålgrundet together. They only have time to drop anchor before a huge ship rises from the depths, a fearsome figure towering over the railing. And in the very next moment, a large fishing net comes flying and covers their small boat. Inexorably, they are pulled towards the great pirate ship…

Nelly Rapp and Captain Bluebeard is the fourteenth adventure in the immensely popular Nelly Rapp, monster agent, series.