While flying in a Taelon shuttle through ID space, a sabotaged interdimensional drive sends Liam and Augur to a parallel universe, where the Taelons are in the process of conquering a very different Earth than the one they know. The Taelons' human enforcers are led by the tyrannical Kayla, who is Lili's Doppelgänger. They make contact with the local La Résistance, led by the kind Jason (Sandoval's double) and his wife Maiya, who is actually Kayla's sister. With the help of the resistance, Liam makes his way aboard the Mothership and talk to Da'an, learning that Ma'el never came to Earth in this reality, which likely serves as this world's Point of Divergence. With Da'an's help, Liam and Augur are able to recreate the accident and return to their own reality, bringing Maiya with them, while Jason is killed by the humans serving the Taelons. Liam convinces the alternate Da'an to work with the Resistance to end the war.
- Alien Invasion: This is what's happening in the parallel world. The Taelons are a lot more militant (to the point where Zo'or and Da'an wear warrior sashes similar to the ones T'than wears in the prime reality. Da'an is also clearly more hostile to humans than his prime counterpart, although he is still less dismissive of them than Zo'or.
- Ancient Astronauts: Averted. Unlike the prime reality, the parallel Ma'el never came to Earth and instead became a great Taelon leader (and Da'an's mentor) until he was forced from power. Liam realizes that the parallel humanity is the true species, having developed free from alien interference, whereas his own world was altered by Ma'el's arrival.
- Artificial Gravity: Kayla uses a gravity pulse to knock the entire Imerian Resistance off their feet. Meanwhile, the Taelon-enhanced humans are able to walk around without any issues.
- Category Traitor: Kayla used to be a member of the Imerian Resistance but chose to join the Taelons in order to become stronger thanks to their genetic enhancement. Apparently, Kayla and Maiya's mother also joined the Taelons, but her goal was to ensure her people's survival. Their mother didn't survive the enhancement process.
- Cruel Mercy: After Maiya beats Kayla in a fight, Kayla asks her sister to kill her. Maiya refuses, wanting Kayla to live out her life knowing that her pure human sister defeated her.
- Curb-Stomp Battle: Despite the parallel humans' advanced weapons, they're no match for Taelon technology. The resistance soldiers open fire with everything they have on the Taelon shuttle, but the shielding easily shrugs off the attack. Kayla then engages the gravity pulse, which causes all the Imerians to drop to the ground, unable to move. They're quickly disarmed and imprisoned.
- Designated Girl Fight: During the escape from the Mothership, Maiya and up fighting Kayla, while Liam handles the other (male) soldiers. Then again, this has been a long time coming, as the sisters wish to fight one another.
- Doppelgänger: Liam and Augur encounter this world's versions of Lili and Sandoval, although they're called Kayla and Jason, respectively. They appear to be complete opposites of their prime world's versions: Kayla is ruthless and is happy to serve the Taelons, while Jason is the kind and friendly leader of La Résistance. This world's version of Da'an is much more militant than his prime world's version, but even here he is much gentler than the other Taelons, especially Zo'or, who appears to be a bastard in every universe.
- Friendly Enemy: Liam manages to convince the Da'an of this world to help him get home and to work with La Résistance to put an end to the war.
- Hopeless War: There's nothing the Imerians, or indeed all the humans of the parallel world, can do to stop the Taelon invasion. They're simply delaying the inevitable. But that doesn't stop many from resisting anyway.
- Meaningful Echo: When Liam is trying to convince Da'an to stop the Taelon invasion of Earth, knowing that he sees humans as equals (thanks to being Ma'el's student), Da'an asks if it's possible for a single being to change the future. Liam has Da'an read his memories, specifically of the conversation he had with his own Da'an in the previous episode about fate. Liam then repeats Prime!Da'an's words back to Mirror!Da'an.
- Point of Divergence: In the parallel world, Ma'el never came to Earth to study humanity. As such, the Taelons were never warned to stay away from the planet and came in force instead of approaching humanity cautiously. In addition, without Ma'el, humanity never built cities and lives in harmony with nature, although this somehow didn't prevent them from developing weapons well in advance of what the prime world's Earth possesses (according to Jason, harmony with nature doesn't mean harmony with each other).
- Rebel Leader: Jason (Sandoval's double) is the spiritual leader of the Imerian Resistance, while his wife Maiya appears to be the military leader. Jason is also highly respected in other parts of the world. Jason is killed at the end of the episode by one of the soldiers. While normally Maiya would lead the Resistance, Jason asks her to go with Liam to protect him, so one of her lieutenants becomes leader instead, with Da'an helping him escape.
- La Résistance: A small group of humans resists the Taelon conquest, but the Taelons' human enforcers outnumber and outgun them. The resistance cell we see is on the so-called "Imerian Continent", which appears to be the west coast of Spain in our world (possibly suggesting that the word "Imerian" comes from "Iberian").
- Underestimating Badassery: Kayla keeps treating the Imerians and her own sister as weak and not worth much. Zo'or keeps chastising her for continually underestimating her own sister, which is ironic given that the prime universe's Zo'or is known for underestimating humans.
- Vehicular Sabotage: An agent sent by Doors sabotages Liam's shuttle, hoping to kill Liam the moment he enters ID space (maybe even Da'an if he's also in the vehicle). However, Liam invites Augur for a joyride. The agent tells Doors about the passenger, but Doors decides to write them both off. Thanks to Augur's tech skills and Liam's piloting experience, they're able to survive, but the sabotaged drive accidentally sends them to a parallel world.
- Vehicular Turnabout: After the entire Imerian Resistance, plus Augur, is taken prisoner aboard the Mothership, Liam and Maiya knock out a pair of soldiers and don their uniforms. Liam hopes to be able to infiltrate the Mothership using one of their shuttles. He tries to put it to Maiya as a "they'll never see it coming", only for her to see right through the bravado and reveal it for the desperate move it is. Indeed, the unknown shuttle is recognized in the hangar mere minutes after they leave it, an alarm is sounded, and they're quickly captured.
