When Batman introduces a new Justice League hopeful, Green Arrow gets suspicious. Who is this new hero and why should they trust him? But his questions are quickly pushed aside when members of the Justice League suddenly start losing their powers. What is going on? Little do they know, a super-villain in their midst has set his sights on the team's Watchtower satellite. Can the Justice League save their headquarters before it's too late? Find out in this action-packed chapter book for DC Super Hero fans!