Old grudges and new enemies emerge as the girls continue the quest to track down their families. Their adventure takes them to the frigid world of a Scandinavian royal court, where a daughter is to meet the mother who abandoned her years ago. When Tristan, a dazzling royal officer, arrives on the scene, emotions come to the surface and hearts are broken. And how will the Storm Sisters reach the place all clues seem to lead: a forbidden land of ice in the deepest, darkest part of the Arctic Ocean?
Charlie, Sadie, Liu, Raquel, and Ingela are five young girls traveling the Seven Seas in search of their missing families, who disappeared on the infamous Day of Destruction. The girls are in great danger from sinister foes, and have created a false identity as a fierce group of pirates. As a vengeful father threatens Liu, the girls must head into uncharted waters. But how long will their disguise keep them from harm? And is it such a good idea to join forces with a group of rebellious boys from their past?
The oldest of the group, Charlie is out to seek justice. She's struggling to find her role as a leader.
Sadie is the healer and book worm of the bunch. She's not really convinced Charlie is the best leader for them.
Escaping from a future prescribed for her by her dominant father, Liu is ready to do anything to keep everyone safe.
Raquel, the diplomat among the girls, is sensitive and calm, but only on the surface.
Despite being the youngest, Ingela is courageous and tough. However, she does have a tendency to misbehave.