Brothers Jacco and Vin and their friends Samantha, Marco and Mo appear to be descendants of an 18th century’s gang of thieves led by a man named Jack. In order to assess whether the children could indeed be the modern Jack’s Gang, they are tested by a group of mysterious regents. Each child is chosen for his or her specific qualities and every test is held in well known haunted places in Amsterdam such as the Historical Museum or the Waag. The group is helped by Gideon, a blind librarian with magical gifts and Agatha, Jacco and Vin’s spiritual aunt. How will this end?