World renowned doctor of engineering Caff who'd always been ridiculed for his small stature disappears one day. He kidnaps Young-hee's father Dr. Yoon who is a physicist. But Hoon, who still hasn't gotten over his failure to save Miran, refuses to get in the control seat of Robot Taekwon V again. However, they rescue Suelle who was chased by Caff's spaceship. But she is actually spy for Caff and she begins to siphon information about Robot Taekwon V's features and technical information. Suelle falls for Hoon but when she is found out by Young-hee, she runs away to Caff. Dr. Yoon researches energy 90 as part of Caff's plans to take over the universe.