The Centurions defend an Arctic base against Doc Terror's forces, but inadvertently uncover a frozen dinosaur which Jake discovers while out on his own after the battle. The dinosaur attacks the base, and the Centurions attempt to stop it. Terror observes the beast heading towards Dominion and captures it, intending to use it against the Centurions. Feeling sorry for the creature, Amber accidentally releases it. It then soon breaks out of Dominion with her and heads towards San Francisco, where the Centurions have to stop it and rescue Amber.

Science Lesson: Polar ice caps by Max.

As the Centurions defend a thermal energy plant from yet another assault by Doc Terror, the berillium crystal on board Skyvault that is a key part of the beaming chamber is fractured. Requiring a replacement, Ace and Jake are sent to a jewellers but find that they have all been bought by a company named Star-Crossed Industries. Knowing that the company is a front for Terror, they decide to go to the mine in Tibet that the crystals originally came from. Once there however, they come under attack from Terror's forces, who have been mining all of the available crystals. With Max attempting to synthesize a new crystal in Sealab, and Ace and Jake unable to access their weapon systems, the Centurions must figure out a way of repairing the beaming chamber before Terror's plans can succeed.

Crystal and the Centurions meet Professor Hartman at a medieval festival. He claims to have discovered the location of Merlin's tomb on an ancient map. They soon come under attack by Doc Terror's forces, who want Hartman's map. Terror wants Merlin's powers, and journeys to his tomb at Stonehenge to reawaken him. The Centurions arrive and protect Merlin from Terror, but he steals King Arthur's crown from the tomb. With the Crown, he summons the sword Excalibur, but it is taken by Hartman's assistant, who is descended from Morgan Le Fay. With Merlin's help, the Centurions try to retrieve Excalibur and defeat Terror.

Science Lesson: Stonehenge by Jake.

Jake is testing out his new Swing-Shot weapon system with Ace, under observation by Klaus, the designer of the Centurions' weapon systems. Crystal detects activity from Doc Terror in the Andes mountains, and Klaus tells the team that they'll need Swing-Shot's abilities under his observation. Once there, the Centurions fight Terror's robot insects, but Swing-Shot freezes up in the middle of the battle. Blaming himself for the malfunction, Klaus later attempts to find out Terror's plan for himself, but ends up being captured. Terror informs him that he wants an Incan emerald to power his mega-laser that will be aimed at Skyvault. He also forces Klaus to improve his ground-borg designs to use against the Centurions. Fighting against their own technology, the Centurions must stop Terror and rescue their friend.

Science Lesson: Hydro-electric power by Max.

A new surface-to-Atlantis rail shuttle is opened by Princess Diana, with the Centurions in attendance. During its inaugural journey, the train comes under attack by Doc Terror's forces and the Centurions engage them in battle. During the fight, Diana's cousin Naro and the evil physicist Phisto escape from Atlantis' prison. Phisto then creates an artificial micro black hole which soon attracts the attention of Doc Terror. After the battle with Terror's borgs, Ace is sent to look for Naro and Phisto whereabouts, but is ambushed by Naro's henchmen and knocked unconscious, now completely at their mercy...

Science Lesson: Micro-technology by Crystal.

Rex attempts to locate the missing Ace but only finds his discarded wristcom and soon comes under attack by Terror's forces. Ace is brought in front of Naro, who plans to take over Atlantis once more. Dr. Terror meets with Naro and plots to take control over the black hole. However Phisto can't control the black hole and it's up to the Centurions to fight Terror's cyborgs, evacuate Atlantis and prevent the growth of the ever-expanding black hole.