The Garde have suffered the ultimate betrayal: Number Five has allied himself with the Mogadorians, killing Eight and helping the Mogs to abduct Ella from the safe house. Now the fight for Earth's survival has just become that much more impossible. The Garde may not have time to mourn their fallen ally, but they'll make sure to avenge him. And help is at hand from the most unlikely of sources: Adam, a Mogadorian, has turned his back on his people. He might just be their lifeline, but are the Garde repeating past mistakes by putting their trust in him?