The timeline is burning. No one knows why. Teenage twins Malcolm and Valentine Gilbert have defeated doomsday machines, ice monsters, and time-traveling supervillains. Yet their full potential remains out of reach. The Chrona is elusive, and without her guidance they struggle to grow in their abilities and to choose the course of their lives. When an enemy invades from the future, he brands the twins as war criminals. Amidst a war between ages, the twins must uncover the real truth about themselves, their accuser, and the secrets that brought him to their town. At all costs, they must unlock their true power before the enemy breaks the timeline completely. If they fail, it could mean the end of Time itself.