Aspen returns to the surface world after making her escape from the Black, but things are not quite the same. Her roommate is gone, and her father, Captain Matthews, has gone missing. Aspen needs some help, and there's only one person left she can turn to. Meanwhile, Marylander's experiments on the hydroport are nearing completion, and his elite team of Tigersharks are preparing for deployment. As the capital city still reels from Saba's destruction, and the council's defense is searching for Cannon, who is left to guard the city?