Grimbor wants revenge on the Legion after the death of Charma in prison.
While still a student at the Legion Academy, Dawnstar recounts her origin and learns teamwork when she tries to round up two escaped creatures by herself.
Grimbor harbors resentment against the Legion of Super-Heroes for having defeated him once before. Grimbor has been obsessed with creating the perfect manacles to hold all the Legion of Super-Heroes, even the powerful Superboy. The Legion answer a call from the President of Earth to find him in a trap that they cannot release him from. They realize this looks like the work of Grimbor the Chainsman when Grimbor arrives and attacks, trapping the Legionnaires in his special manacles. Holding the Legionnaires captive, Grimbor explains how Charma was killed in a female prison and that has fueled his obsession about capturing the Legion. The Legion escape and fight Grimbor, who is revealed to be a robot, and they race to the President to free him. They soon find the real Grimbor and send him to jail.
Story 2: Dawnstar Rising
This story delves into the past of Dawnstar, back when she was a student in the Legion Academy.