22 episodesFirst aired 8 October 2004
Upon returning home after preventing a second Xindi attack, Enterprise explores cultural shifts on Vulcan; forges alliances with Earth's neighbors in the face of Romulan aggression; deals with a plague inside the Klingon Empire; explores the Mirror Universe; and overcomes xenophobic elements to lead an interstellar community.
E1Oct 200443m
Archer and the NX-01 find themselves in Earth's past, with events of World War II altered by the Temporal Cold War.
E2Oct 200443m
With Silik's help, Archer hones in on the temporal operative who altered Earth's past and threatens to destroy all of time.
E3Oct 200443m
Once the NX-01 finally returns to Earth, the weary crewmen face repercussions of their journeys, both positive and negative.
E4Oct 200443m
When genetic supermen left over from the Eugenics Wars hijack a Klingon ship, Archer must rely on their creator, the criminal Dr. Arik Soong, to help hunt them down.
E5Nov 200443m
Arik Soong leads his band of Augments to a medical facility where hundreds of genetically enhanced embryos are still stored, intending to retrieve them and bring them to life.
E6Nov 200443m
In defiance of their "father," Arik Soong's Augments devise a heinous plot against the Klingons which will surely lead to interstellar war.
E7Nov 200443m
Earth's embassy on Vulcan is bombed, and the ensuing investigation puts Archer and T'Pol on the trail of a Vulcan religious faction hiding in a treacherous desert.
E8Nov 200443m
Archer and T'Pol encounter the Syrrannites, a radical group hiding in the Vulcan desert, while the NX-01 crew contends with Vulcan power ploys.
E9Dec 200443m
Archer, T'Pol and T'Pau attempt to bring the Kir'Shara — an artifact believed to contain Surak's original writings — to the Vulcan capital, as the NX-01 gets involved in a Vulcan-Andorian military clash.
E10Jan 200543m
The inventor of the transporter, Emory Erickson, comes aboard Enterprise for a risky experiment.
E11Jan 200543m
Non corporeal aliens study the Enterprise crew as they respond to a fatal viral infection brought on board from an away mission.
E12Jan 200543m
Enterprise journeys to Babel with a Tellarite ambassador on board for peace talks with the Andorians, when a distress call from Shran is received.
E13Feb 200543m
Archer tries to unify the Andorians, Tellarites and Vulcans in a plan to capture a marauder ship threatening to destabilize the region.
E14Feb 200543m
Archer visits Shran's icy homeworld to find an Andorian subspecies called the Aenar, to determine their connection to the marauder destroying ships in the region.
E15Feb 200543m
While Enterprise visits Earth for the launch of Columbia, Phlox is kidnapped and forced to help the Klingons deal with a grave threat toward their species.
E16Feb 200543m
With Columbia's help, the Enterprise crew grapples with sabotage to their ship as they pursue the truth behind the kidnapping of Phlox.
E17Apr 200543m
As a gift for negotiating with the Orion Syndicate, Captain Archer receives three Orion Slave Girls.
E18Apr 200543m
In the mirror universe, Commander Archer mutinies against Captain Forrest in order to capture a future Earth ship found in Tholian space.
E19Apr 200543m
In the mirror universe, Archer commandeers the 23rd-century Defiant from the Tholians and uses it in a nefarious power grab.
E20May 200543m
A xenophobic faction of humanity threatens to undermine talks to form a new coalition of planets.
E21May 200543m
A human isolationist leader threatens to destroy Starfleet Command unless all aliens leave Earth immediately.
E22May 200543m
Six years in the future, an emotional Captain Archer and the crew return to Earth to face the decommission of Enterprise and signing of the Federation charter.
