Daniels sends Archer and T'Pol to 2004 Detroit to follow three Xindi-Reptilians who are creating a biological weapon.
An alien race known as the Xindi launch an attack on Earth, causing great casualties and massive damage. As Enterprise heads back home, an unlikely source informs Archer about the Xindi and that their next attack will destroy Earth.moreless
Enterprise visits a planet where an Interspecies Medical Exchange conference is being held. Dr. Phlox tries to obtain research on a terminal disease from the Vulcan contingency, without revealing T'Pol has been infected by it.moreless
After T'Pol is contacted by the Vulcan High Command, Archer, Mayweather and T'Pol travel to an arctic world to apprehend a fugitive. The mission takes a dangerous turn when T'Pol begins to have flashbacks that suggest the events she remembers about a former mission may not accurately relate to what happened.moreless
In need of fuel, Enterprise visits a mining colony for deuterium supplies. The crew discovers that the colony is being controlled by Klingon marauders who are regularly pillaging the mined deuterium.
Archer spends a night in sickbay after Porthos falls ill with a deadly virus following a visit to an alien planet.
After Archer and Trip become curious about a visit T'Pol made to a Pennsylvanian mining town called Carbon Creek, she tells the two a tale about a Vulcan ship that crash-landed in 1957.moreless
Enterprise is sent to the planet Mazar to pick up a Vulcan ambassador who has been expelled for misconduct.
A strange, alien creature comes aboard Enterprise, and captures several crew members in its cocoon-like web. With her crewmates' lives in jeopardy, Hoshi faces her biggest challenge yet, in trying to communicate with the lifeform, in order to return it to its home planet.moreless
While searching for components to repair Enterprise, crew members encounter ghostly beings aboard a crashed vessel.
Enterprise encounters alien pirates who use a booby-trapped artifact to gas the crew into unconsciousness, then pillage the ship for treasures.
While exploring an uncharted planet, Enterprise crew members encounter a group of aliens who are hunting down indigenous creatures for recreation. During their exploration, Archer is mesmerized by visions of an elusive, yet familiar woman who needs his help.moreless
Enterprise encounters a group of Vulcan civilians who have split off from the normal way of Vulcan life in an effort to explore their emotions. T'Pol is disturbed by the new visitors and warns the Captain that all attempts in the past to integrate Vulcan emotions into their lives has proven disastrous. Meanwhile, a message from Admiral Forrest leaves the Captain with the difficult task of trying to convince one of the visiting Vulcans to call home to speak with his dying father.moreless
Tucker and Reed set out on a mission in a shuttlepod, as Enterprise is busy investigating an asteroid field. Disaster strikes while the pair are away, leaving the shuttlepod damaged and the warp drive inoperable. They manage to make it back to the rendezvous coordinates only to discover that Enterprise has apparently been destroyed. With the ship seemingly no more, the pair are left abandoned in the middle of nowhere with only a few days of air remaining.moreless