The Forge of Creation
As the fourth season begins, Lili Marquette (Lisa Howard) gives birth to a child that may be the last hope for survival of the Jaridians.
Sins of the Father
Renee (Jayne Heitmeyer) and Liam (Robert Leeshock) discover Da'an (Leni Parker) is addicted to Kryss, a substance used by Taelons to help them adapt to Earth's atmosphere.
Renee and Liam investigate the link between Zo'or and a biomedical facility's clandestine cloning operation.
While deceased Doors International President Jonathan Doors resurfaces in cyber form to deliver a potentially deadly blow to the Taelons, an alien murder aboard the mothership reveals to Liam the Taelons' darkest secret.
An amoralist's plan to steal a fortune in gold from Zo'or puts Augur's life in jeopardy.
Take No Prisoners
The discovery of a deadly parasite, believed to be extinct, threatens an amnesty for all Resistance members that has been negotiated by the Atlantic National Alliance.
Chaos erupts when the Taelons decide to abandon Earth in the face of imminent Jaridian invasion.
Renee's younger brother, Richard, falls victim to Zo'or's plot to harness human emotions.
While onboard the Mothership, Renee is taken hostage by a mysterious being who haunts the secret chambers of the vessel.
Earth: Final Conflict
Liam and Renee track a serial killer who invades people's dreams to commit murder.
Liam and Renee suspect Taelon wrongdoing when a human baby is born with a CVI implant.
Liam Kincaid copes with a neural surveillance implant while trying to track Da'an, who leaves Earth on a mysterious "final" journey.
The future of the Taelons looks bleak after a mysterious piece of dark matter collides with the Mothership. As a result of the collision, Zo'or is sent into some kind of stasis. Meanwhile, Liam and Renee are appearing before a presidential committee, suggesting a coup to oust Zo'or and make Da'an the leader of the Taelon Synod.
News of the incident reaches Liam, and he meets with Da'an. Da'an explains that the dark matter must be expelled from the ship, or it will destroy it and everyone onboard. At the same time, Sandoval plans to recall all the Taelons to the Mothership, kill them, strip the ship of anything of value, and send it to Jaridia!
Liam races to the Mothership to get rid of the dark matter with a photon bomb, but he is captured by Sandoval and Frank Tate. Just when it looks like the Mothership is going to shut down, killing everyone inside, Ha'Gel appears to Liam, telling him that he can use his Kimera energy to save the ship, but he will become fully human if he does. Liam touches hands with Ha'Gel, destroying the dark matter and rendering him completely human.
Keys to the Kingdom
Zo'or threatens to attack Earth after an artifact containing the secret of synthetic core energy is stolen from the Taelon Mothership.
While trying to elude Sandoval, Street learns a lesson in trust.
Trapped by Time
The fate of the Earth and the Taelons may be revealed when three astronauts from the future are discovered in stasis within a top-secret government base.
In exchange for full immunity, Sandoval agrees to testify that the Taelons have committed atrocities against the human race. Renee and Gre Van Hoeck, an ANA prosecutor, meet Sandoval to take him into protective custody, when an assassin appears and shoots him in the chest. Liam arrives and drives the shooter off, and Sandoval is not fatally injured.
When Sandoval increases his demand for immunity to include relocation and 50 million gold marks, the grand jury balks and he is put on trial for crimes against humanity. During the trial, Zo'or fires an energy data stream into the situation room where the proceedings are being held. He demands that Sandoval be returned to the Taelon Mothership, or he will being firing proton missles at Earth. He is returned as asked, and Zo'or forgives him, telling him that it is time he realized Zo'or is the only friend he has.
Liam and Renee suspect Zo'or of orchestrating a series of murders.
Hearts & Minds
Renee is torn between love and duty when her boyfriend (Jeff Marlowe) is captured by the Taelons.
In the fourth season finale, The Taelons' impending death stasis sparks a battle of wills between Da'an and Zo'or. A full writeup is available.