Scorpius is a half Sebacean, half Scarran who was working on unlocking the secrets to creating wormholes for the Peacekeepers when he notices an imposter on the gammak base. It's John Crichton, posing as Larraq in order to find a tissue sample of periferal nerve to save Aeryn's life. Scorpius subjects John to his aurora chair to view his memories and discovers that Ancients have given John wormhole knowledge. He believes John is trying to withhold wormhole secrets from his aurora chair when John escapes his grasp.
Scorpius makes a point to pursue but seems very patient, as John now holds an implant of a neural clone of Scorpius, one John will soon discover and deem Harvey. Scorpius takes over the command of Crais' command carrier. Crais escapes aboard the Leviathan warship Moya has given birth to, Talyn. Once again John escapes Scorpius' grasp.
Scorpius continues his pursuit with John constantly evading him until Scorpius has found himself in yet another coup for the command carrier. Crais destroys the carrier by Talyn starbursting within it and Scorpius is taken into the grasp of John's new pursuer, Commandant Grayza. To escape Grayza and protect John's precious wormhole knowledge from the inevitable confrontation with Scarran's, Scorpius manages to board and remain on Moya with Aeryn's assistance.
While on board Scorpius meets Sikozu, seeming to be his soul ally besides Braca. After John does encounter the Scarran's, John nearly leavs Scorpius to fend to his own in their capture until the Harvey clone returns to coerce John into Scorpius rescue, rather than see his knowledge such as the location of Earth and wormholes, in the hands of the Scarrans. Scorpius becomes rather obsessed with seeing the end to a very precious plant to the Scarrans aboard the base that the Scarran royalty eat. It looks like the Birds of Paradise plant on earth which in thier history has been eaten to progress Scarran's intelligence.
Once the mother plant has indeed been destroyed, John kicks Scorpius and Sikozu off of Moya. They return to a new command carrier within the care of Braca, who has relinquished Grayza of command for attempting to make irrational decision.
