The four Melkerson children are a little bit worried on reaching Seacrow Island, where their father has rented a cottage for the whole summer without even setting eyes on it. On the boat a man told Pelle, the youngest Melkerson, that the cottage’s roof leaks. They disembark in the pouring rain. Seacrow Island, however, turns out to be full of all sorts of wonderful surprises. Pelle loves animals, and here he finds Bosun, the most gigantic dog he’s ever seen, along with his irrepressible owner, Tjorven. Johan and Niklas meet Teddy and Freddy, two girls, as it turns out, who know all about boats and exploring. As for nineteen-year-old Malin, she falls in love for the first time. By the end of the summer, all four children and their father know that Seacrow Island is home.