Crichton is reunited with Chiana and Rygel in an attempt to save a dying Leviathan from a group of mercenaries, who storm his new home in an attempt to harvest the living ship's flesh.
More of Moya's crew is reunited on a planet where Interion scientists are conducting an archeological dig. But their happy reunion is threatened when Commandant Grayza arrives and puts Crichton under a sensual spell.
The crew must stop the Peacekeepers from uncovering an alien weapon of mass destruction, while Crichton fights against Grayza's intoxicating allure.
The crew searches for Moya, but an emergency landing strands them on a desolate planet, where a group of mercenaries capture Rygel inside a lava-filled cavern.
The crew returns to Moya, where they find that Aeryn has returned -- struck with heat delirium. And when a massive alien vessel comes looking for her, Crichton and the others must outwit their opponent to save her life.
Moya is attacked by a large, space-faring organism that attaches to the hull and penetrates her systems.
John and Chiana are trapped in a virtual reality simulation, and must win a game controlled by an unstable Stark while Moya may be in danger of attack from within.
A gang of ruthless bounty hunters seize control of Moya in order to capture Crichton, and shrink the crew to keep them prisoner.
The crew seeks assistance on a world ruled by warring clans working toward a tenuous peace, but Aeryn is accused of assassinating their next leader.
An alien doctor blackmails Moya's crew by poisoning them with deadly mollusks.
Crichton falls into a wormhole and is found by an interdimensional being, who must decide whether or not to execute him because of the threat that his knowledge of wormholes presents to the universe.
Crichton returns to Earth, only to discover that he is more than 15 years in the past and his father has accepted command of the doomed Challenger mission.
Crichton makes his grand return home, where he and his alien friends introduce Earth to the larger universe that awaits them. Meanwhile, Grayza dispatches an alien chameleon to hunt Crichton
Chiana purchases a slave girl from a passing trading ship, but the crew quickly learns that Talikaa may not be as innocent as she seemed.
Scorpius takes Crichton, D'Argo and Rygel into an advanced training camp where students learn mental discipline. D'Argo is confronted with the arrival of Macton (the peacekeeper that murdered D'Argo's wife and framed him for her death).
While purchasing a camouflage device for Moya Aeryn and Sikozu witness the nearby landing of a Peacekeeper squad led by Grayza and Braca. Chiana and Noranti choose to undergo genetic manipulation to elude the shearching the Peacekeepers. Aeryn and Sikozu spy on Grayza who has convened a secret meeting with Scarran emissaries.
Having overheard Ahkna (the Scarran Minister of War) mention the secret Scarran base known as Katratzi sikozu is sure this is where the Sarran intend to take Aeryn. Though Moya's data banks have no record of Katratzi, Crichton is sure hehas heard the word Katratzi somewhere before.
Aeryn is being held captive aboard a Scarran feighter captained by Jenek who is determined to find out if Aeryn's carrying Crichton's child. To discover the location of the Scarran base where Aerin is being taken, Crichton and Scorpius travel through a wormhole to an "unrealized reality".
Moya's crew tracks Aeryn to a Scarran Border Station where the freighter she is imprisioned upon is about to leave for Katratzi. To keep the ship docked and under quarrantine Noranti gives Rygel s deadly and contagious disease. Though this gives them time to come up with a plan to rescue Aeryn they don't figure on the cunning and ruthlessness of Aeryn's Scarran captor: Jenek.
The crew travels to Katratzito save Scorpius that is being tortured for the wormehole information. The base is the home to the Halish and Charrid forces (underlings the Scarrans). The crew plans to incite a confrontation beteween the Halish and Charrid hoping to distract the Scarrans so that they can save Scorpius and prevent the Wormehole knowledge to fall into Scarran hands.
After thwarting Crichton's escape plan Scorpius denies that he is a Scarran spy and demands Crichton's help to destroy a cavern of vital Scarran flora. Scorpius clams that destroying the flora will provide them with a better means of escape. Meanwhile Rygel and Noranti fight an evil Stark.
Now safely back on Moya, Crichton learns that the Scarrans are planning to attack Earth. He feverishly analyzes his wormhole data and comes up with a way to collapse the wormhole to Earth but he can't do it alone. Meanwhile, Braca demands Scorpius to be released from Moya and returned safely to his Command Carrier.