Cookies help us deliver our Services. By using our Services, you agree to our use of cookies. Learn More.

The 25 Best Episodes Of Star Trek: Enterprise Ranked

A radical departure from the previous four "Star Trek" series, the 2001 spin off "Star Trek: Enterprise" was a prequel series set barely a hundred years after Earth's first contact with extra terrestrials. Before the founding of the United Federation of Planets, before Earth had fleets of powerful starships, phasers, or even transporters, "Enterprise" chronicled the first experimental Warp 5 ship (the titular Enterprise) and its mission to explore the final frontier. While Earth's only alien friends, the Vulcans, remained skeptical of humans' ability to navigate interstellar affairs, Captain Jonathan Archer — consummate explorer — sets out to prove them wrong.

While the first two seasons were mostly standalone adventures that harkened back to classic "Trek" of old, Season 3 embraced a season-long story. It introduced the Xindi into the franchise as a nefarious new alien race comprised of five different species plotting to destroy Earth. The fourth season would be ambitious, turning to a series of multiple-episode stories that dipped into classic "Star Trek" mythology, too. Though never a hit in the ratings department "Star Trek: Enterprise" is better than you might remember. It was unceremoniously canceled before it could make its fifth season, but the show has a number of gems from throughout its run. This is a list of its 25 best.

25. Dead Stop (Season 2, Episode 4)

In "Dead Stop," Archer and Enterprise are still badly damaged from their disastrous brush with a Romulan mine in the previous episode. With no starbases in this era, the ship is on its own, and the captain begrudgingly puts out a general distress call for help. A passing Tellarite ship alerts them that there is a nearby space station where ships often travel for repairs, and so Archer sets off to find it. After a three day journey they discover an unmanned, automated repair station that offers to fix up their starship in exchange for some expendable supplies they have on-hand.

Equipped with incredible replication technology and even a recreational lounge for the crew to spend their time in during the repairs, the station seems too good to be true. While Archer is suspicious of their good fortune, Tucker and Reed get curious about the station's inner workings — and come across mysterious chamber they can't access. But Archer's suspicions are confirmed when Ensign Mayweather turns up dead, and they suddenly realize that there may be more to the helpful station than mere repairs.

24. Damage (Season 3, Episode 19)

In classic "Star Trek" fashion, the crew of Enterprise are faced with an impossible ethical and moral choice in the Season 3 episode "Damage." Former "Deep Space Nine" star Casey Biggs guest stars as the captain of an alien vessel who comes to the aid of Enterprise, which is limping through space after a Xindi attack. Heavily damaged, Enterprise is losing life support — and with no warp coil and thrusters inactive, the ship is functionally adrift. 

The life-saving chance encounter with the Illyrian vessel is a boon to Enterprise, but their emergency assistance isn't enough for Archer. The Enterprise captain demands that the Illyrian ship hand over their warp coil so they can continue their mission. The alien captain refuses, as it would leave them stranded just like Enterprise. Determined to stop the Xindi at any cost, Archer wrestles with whether to steal the coil and complete their mission, believing that crossing a moral line is justified when billions of lives are stake. The Xindi Council, meanwhile, debates their confrontation with Archer, with Degra and his allies beginning to question their quest to destroy Earth. 

23. Awakening (Season 4, Episode 8)

Part two of a three part story set on Vulcan — a rare extended look at the planet of Spock's origin – "Awakening" sees Archer and T'Pol finally make contact with the rebel Syrannites who live in The Forge. Their leader, a woman named T'Pau (a character seen in "Star Trek: The Original Series episode "Amok Time" as an elder Vulcan priestess) maintains her innocence in the bombing of the Earth Embassy. T'Pol is skeptical, having heard of the radical Syrannites ways. T'Pau too is distrustful of Archer and his Vulcan companion, suspecting them of being the terrorists themselves.

But upon learning of the death of the Vulcan named Arev, T'Pau tells them that he was in fact their leader Syrran, who possessed the katra — the living soul — of Vulcan's messiah Surak. As unbelievable as it sounds to Archer, T'Pau believes that Syrran may have transferred the katra to him before his death, and its now up to her to retrieve it to save the future of their world. Meanwhile on Enterprise, Soval attempts to get to the bottom of the terrorist attack via the use of a mind meld, which gets him into trouble with V'Las, the leader of the Vulcan High Command, who believes the ancient ritual is blasphemy.

22. Terra Prime (Season 4, Episode 21)

Before starring as Admiral Marcus in "Star Trek: Into Darkness," actor Peter Weller first appeared as another corrupt militant Earth leader in what many see as the real "Enterprise" series finale, "Terra Prime." A fitting conclusion to the overall premise of the series, the episode concludes a two-part story that began with a xenophobic mining leader named John Frederick Paxton (Weller), who is enraged at the prospect of Earth entering into an interstellar alliance. In response, Paxton and his radical extremist group called Terra Prime have turned the Mars-based verteron array into a weapon, and threaten to unleash it on Earth unless every alien is forcibly expelled from the planet.

As part of his plan to frighten the people of Earth, Paxton also genetically engineered a baby using the DNA of Trip and T'Pol, creating the first Vulcan/Human hybrid. With Enterprise called in to deal with the crisis, Archer's two officers have an added personal incentive to stop the madman, seeing the baby as their own daughter, and hoping to rescue her from Paxton's clutches. But stopping Terra Prime and signing the first charter of the Coalition of Planets won't be an easy task, as the crew discovers that Paxton and his followers aren't the only ones nervous about galactic peace.

21. Strategem (Season 3, Episode 14)

At the height of the war with the Xindi, Archer hatches a diabolical scheme to steal enemy secrets in the mind-bending psychological thriller "Strategem." Aboard a Xindi shuttle, the villainous Degra awakens to find Archer with him, disheveled and exhausted. They're being pursued by Xindi Insectoid patrol ships. Degra has no memory of how he got aboard the craft, but Archer explains that the Xindi plan to destroy Earth was a success, but in its wake, the Insectoids launched an assault on the other factions. Turning on the their Xindi races, they imprisoned Degra, and Archer claims that the two of them have been cellmates in a Xindi prison for the past three years. Having escaped captivity just recently, a drug used for interrogation has erased his memory.

But as the their escape from Xindi space continues, Degra becomes increasingly suspicious of Archer's story. And he's right to be — it's soon revealed that the shuttle is all part of an elaborate deception to trick Degra into revealing top secret Xindi intelligence. As Degra tests Archer on his claim that they are now friends and allies, Archer's plan begins to unravel, forcing him into more and more drastic measures. But can Archer get what he needs before Degra discovers the truth?

20. Future Tense (Season 2, Episode 16)

A seemingly alien shuttlepod is discovered in "Future Tense." When it is brought on board, clues to its origins only raise more questions. After examining the vessel, it's determined to not be alien at all, but an Earth pod from the distant future, sent back in time for unknown reasons. The puzzle is further complicated when both the Suliban and the peculiar Tholians come looking for the craft, and are willing to kill to get it. Looking for information on what looks more and more like a part of the Temporal Cold War, Archer examines the future database left behind by the mysterious time agent called Daniels.

Though T'Pol remains skeptical of all things time travel related, the vessel in their launch bay starts emitting unusual readings. These readings cause a brief temporal anomaly aboard Enterprise, preventing further investigation into the apparent time pod. As a small fleet of Suliban ships close in, a Vulcan combat cruiser comes to Enterprise's aid and engages the Tholians. With Enterprise outnumbered, T'Pol wants the pod destroyed, while Archer wants to use it as a means to become a more active participant in the Temporal Cold War.

19. The Forge (Season 4, Episode 7)

The first part of the three part Vulcan Syrannite saga, "The Forge" begins with a terrorist bombing of the Earth Embassy on Vulcan. The likely culprits are a rogue faction of Vulcans called Syrannites, followers of a man named Syrran, who takes a different interpretations of the teachings of the Vulcan religious figure Surak. With Enterprise being the nearest Earth ship to Vulcan, Archer and crew head to the planet to assist in the investigation. T'Pol and Archer set out on foot to the Vulcan Forge — a desolate region of the planet that's impenetrable to scanners — where the Syrannites are said to make their home.

During their trek, the pair are saved from a deadly animal attack by a traveler called Arev, who claims to be on a religious pilgrimage. But after continuing on their journey together, Archer and T'Pol become distrustful of the man, and he of them, as there is much more to Arev then it would seem. Meanwhile back on Enterprise, Ambassador Soval is investigating the bombing himself and begins to wonder if the Syrannites are actually responsible. To get to the truth, Soval considers using a forbidden Vulcan ritual that could threaten his position ... and his life.

18. The Expanse (Season 2, Episode 26)

The explosive Season 2 finale "The Expanse" opens with the Enterprise being recalled to Earth after a shocking and devastating attack by the Xindi, a mysterious alien race. Using a massive sphere-like weapon, the Xindi blasted the North American continent, killing more than seven million people. Trip's sister Elizabeth was revealed to be one of the victims of the disaster, making it a doubly personal tragedy for the crew, who are now set on revenge against a new, bloodthirsty enemy. 

Visited by the shadowy future figure, Archer is informed that the Xindi's attack was a pre-emptive strike after a faction in the Temporal Cold War told them that humans would one day destroy their homeworld. With the Vulcans sympathetic but uninterested in a war, and no other Warp 5 vessels in their fleet, the Enterprise is on its own to find the Xindi and confront their latest foe. But locating and getting to them is easier said than done, as their native star system resides on the other side of the Delphic Expanse — a vast region of space littered with dangerous spatial anomalies. And the Xindi aren't the only ones out to get them.

17. The Aenar (Season 4, Episode 14)

"The Aenar" is the dramatic finale of a three-part Season 4 story that puts the focus on the Andorians. After discovering that a Romulan drone ship is being piloted by an Aenar — a mysterious sub-race of ice-dwelling Andorians with powerful telepathic abilities — Enterprise, with the help of Commander Shran of the Imperial Guard, head to Andoria to learn more. Amidst the planet's subterranean ice caves, they find Jhamel, an innocent Aenar girl whose brother had been recently been abducted — and may be a slave to the Romulans.

The Romulan plan to use the drone to instigate a full scale war between Andorians, Vulcans, Tellarites, and Terrans, is slowly unravelling — forcing Senator Vrax to push Valdore to more extreme measures. Aboard Enterprise, Phlox and Reed work together to build their own drone interface so they can commandeer the Romulan ship and turn it against them. But to use it, they'll need their own telepathic pilot. They may have found one in Jhamel, but to complete her mission and stop the Romulans, she may have to make a terrible sacrifice.

16. Shockwave, Part 2 (Season 2, Episode 1)

After the Season 1 finale ended on a cliffhanger, "Shockwave, Part 2" picks up aboard Enterprise with the Suliban in pursuit and looking for its captain — who is nowhere to be found. Outgunned and overmatched, T'Pol surrenders the ship and allows the Suliban to search the vessel, much to the dismay of Tucker. Meanwhile, Archer has been taken forward several hundred years into the 31st century by Daniels, where a change in the timeline has resulted in the destruction of Earth's entire civilization. Getting back to fix history is a problem, however, because every time portal has been destroyed.

Back on Earth in the 22nd century, Admiral Forrest fights with the Vulcan High Command, who demand that Enterprise be recalled, believing they're guilty of destroying the mining colony on Paragaan II. While Forrest is steadfast that Archer is innocent, Soval sends a Vulcan cruiser to intercept them. But with Archer stuck in a devastated future, and T'Pol at the mercy of the Suliban in the present, the fight to prove their innocence may be the least of their problems.

15. In A Mirror Darkly, Part 2 (Season 4, Episode 19)

"In A Mirror Darkly, Part 2" finished up one of the most daring two-parters in the series, a story set entirely within the confines of the parallel Mirror Universe. In the conclusion, Archer has taken command of the future USS Defiant — the same class as the original 1966 Enterprise — discovered in Tholian space. Now in command of the most powerful Earth vessel in their time, Archer easily destroys the Tholians. But when Admiral Gardner arrives to take the ship, Archer defies orders and kills his superior, now intent on returning to Earth and declaring himself Emperor. 

But soon Archer must face enemies both from within and externally, as cutthroat members of his own crew attempt to overthrow him, and non-humans Phlox, Soval, and T'Pol plot to fight back against the fascist Starfleet. A twisted alternate reality adventure with deep ties to the classic "Star Trek" series, it's both a fun nostalgia trip and a nail-biting thriller unlike anything the franchise has ever seen. With a dramatic twist ending, it has become a favorite among longtime fans for far more than its faithful recreation of the original classic starship.

14. The Council (Season 3, Episode 22)

"The Council" follows the events of "E2," where Degra agreed to escort Archer and Enterprise to the Xindi Council. There, Archer will show them his evidence that they are being manipulated by the mysterious race of Sphere Builders and that Earth is not their enemy. Though they are able to convince Dolim to let them pass, the Reptilian Commander remains deeply skeptical and distrustful of Archer's motives. When they arrive, the rest of the council is equally cautious, and want real proof that the Sphere Builders are not truly their allies if they are to call off their attack on Earth.

Aboard Enterprise, T'Pol puts together a team to infiltrate one of the enemy spheres to get more information on its systems in the hopes of finding a weakness. Taking one of the MACO officers with them, T'Pol, Reed, and Mayweather successfully get what they're after, but at a high cost. Back at the Council, Dolim gets his revenge for the destruction of the Reptilian ship.

13. Similitude (Season 3, Episode 10)

While making their way through Xindi space, Tucker is near-mortally wounded in "Similitude." Unable to lose their chief engineer on such a critical mission, Doctor Phlox puts Trip in stasis and comes up with a radical treatment. To save him, Phlox will use a rare species of larvae to create a rapidly aging clone of Tucker with just a two week lifespan, allowing them to use its neural tissue after its natural death. Though Archer and Phlox struggle with the ethics of bringing a life into being just to harvest its organs, they ultimately agree that the stakes are too high to be concerned with the moral dilemma.

The problems begin however when the clone — nicknamed "Sim" — develops into his own person. In just a matter of days, Sim becomes a valued member of the crew and must come to terms with who and what he is. But with many of Trip's own emotions and faint memories, he develops friendships with his crew mates and even begins to fall in love with the ship's resident Vulcan science officer. A classic examination of ethics as only "Trek" can do it, the episode also serves as a turning point in the relationship between Trip and T'Pol. 

12. Shockwave, Pt. 1 (Season 1, Episode 26)

In "Shockwave, Pt. 1," Archer takes Enterprise to a distant mining colony on the planet Paraagan II. During their trip to the surface, an apparent shuttle accident ignites the planet's atmosphere, killing everyone on the planet's surface. In the wake of the accident, Starfleet recalls Enterprise and officially ends their mission to explore deep space, with the Vulcans lack of faith in Archer's command now seemingly justified. But while Archer struggles with guilt over the deaths of the colonists, taking the full weight of the blame, he's suddenly transported into the future where he meets crewman Daniels. 

There, the enigmatic time agent tells him that the destruction of Paraagan II was never supposed to have happened, and that someone has begun meddling with history. Knowing he wasn't responsible for the accident, a reinvigorated Archer sets out to prove his innocence and stop the Suliban from interfering with Enterprise's mission. With evidence of alien involvement in the disaster, Archer must get the information to Starfleet — but they're suddenly stopped in their tracks by a fleet of enemy ships, who demand Archer be handed over to them.

11. Proving Ground (Season 3, Episode 13)

"Proving Ground" continues Archer and Enterprise's mission through the Delphic Expanse. Having lost much of their data that has helped them navigate the region, they're in for a rough road ahead. Just when they get themselves into trouble, an Andorian ship appears. It's commanded by their old friend Shran, who claims he's there to help them find the Xindi weapon. While he insists his motives are pure, Archer suspects there's something else going on. But he's in no position to decline the offer, and they begin working together to investigate the site of the Xindi's prototype weapon.

With a daring plan to raid the Xindi's test site, Archer's suspicions are confirmed when Shran reveals his real plan: to steal the Xindi weapon for himself. Long at war with the Vulcans, Shran believes the weapon will make the difference in their conflict. But Archer wants to destroy the weapon, and will do whatever it takes to prevent it from falling into another's hands — even if it means an end to his new alliance with the Andorians.

10. Kir'Shara (Season 4, Episode 9)

The final part of the 3-part Syrannite saga, "Kir'Shara" the Vulcan High Command starts a war on two fronts, with their star fleet preparing to attack Andoria, while agents on Vulcan are hunting the rebel Syrannites. Soval, aboard Enterprise tries to warn the Andorians, but only succeeds in angering Shran, who believes the Vulcan Ambassador is setting him up. Tucker, in command of Enterprise, attempts to broker a truce, but soon becomes the Vulcans' next target.

At the same time, T'Pol and Archer — thanks to the katra of Surak in his head — have helped T'Pau and the Syrannites locate the Kir'Shara, the mythical artifact said to contain the Vulcan leader's original true teachings. Believing the relic's discovery will bring about a reformation and new period of enlightenment for their people, they hope to return it to the Vulcan High Command before and avert the war with the Andorians. But to get it back, they'll have to evade the attack parties working for the corrupt Vulcan leader V'Las. T'Pau, meanwhile, also believes she can cure T'Pol's Pa'nar syndrome with a mind meld, but the Enterprise's science officer is skeptical of the ancient and taboo ritual.

9. In A Mirror, Darkly, Pt. 1 (Season 4, Episode 18)

In part one of a two part story, "In A Mirror, Darkly, Part 1" begins in the middle of the final scene of the movie "Star Trek: First Contact," when Vulcans first landed on Earth and met humans. But instead of embracing the alien visitors, Zephram Cochrane attacks them and raids their ship. Flash forward a century and we meet Captain Forrest and his first officer Jonathan Archer of the ISS Enterprise. Archer claims to have gotten word of an incredible starship detected in Tholian space and proposes a mission to steal it, believing it to be the key to ultimate power. 

When Captain Forrest declines the mission, Archer overthrows his captain and takes command of Enterprise. With a new team in place, Archer believes he's safe from mutiny and sets out to uncover the secret of the rumored starship. When they arrive, they find the ship contains wondrous futuristic technology, and realize it may be from an alternate reality more than a century in the future. But to get to it, Archer must overcome the Tholian's deadly web and ferret out a saboteur who is attempting to free Captain Forrest and retake Enterprise.

8. Babel One (Season 4, Episode 12)

Archer and Enterprise play peacemaker in "Babel One," part one of a three part story from the series' fourth and final season. The ship is escorting a Tellarite ship to Babel One, where Ambassador Gral will take part in a trade summit. Relishing playing a bigger part in galactic affairs, Archer's escort mission is disrupted by a distress call from an Andorian vessel, under attack from an unknown ship. But when they arrive, it's too late — two Andorian ships have been destroyed. Andorian Commander Shran comes aboard with accusations that the Tellarites are responsible.

With the Tellarite Ambassador onboard, Shran wants revenge, and the two make threats against each other. As Archer attempts to keep them separated until they can get to the bottom of what's happened, Enterprise comes under attack from what appears to be an Andorian ship. But a discrepancy in energy readings leads T'Pol to believe a third party might be involved, attempting to incite a war between galactic powers in the region. With both Gral and Shran skeptical, Archer must find out what's really going on before Gral and Shran start a war between their people.

7. United (Season 4, Episode 13)

"United" direct follow-up to "Babel One" and the second part of a three-parter that sees an unknown ship attacking various alien ships the region — including Terran, Tellarite, and Andorian vessels — in an apparent attempt to sow division and distrust between their peoples. We quickly discover, however, that it's the Romulans responsible for the attacks, using a new marauder drone ship developed by Admiral Valdore and overseen by a high-ranking Romulan Senator. The ship uses a telepathic pilot, but their plans begin to collapse when Tucker and Reed are able to get aboard the unmanned ship and sabotage its systems.

Back on Enterprise, Archer believes he can expose the Romulan's plot, but he'll need more than 100 starships to establish a surveillance grid between them to do it. To get a fleet of that size will require the help of the Vulcans, Andorians, and Tellarites, in a mission that will test their trust. But if it works, it will thwart the Romulans, and perhaps even lead to a newfound cooperation between the longtime rivals.

6. Regeneration (Season 2, Episode 23)

Set more than 200 years before the Enterprise-D's first run-in with the Borg, "Regeneration" might seem like a continuity breaker, but a clever time travel twist allows the Borg to make their presence known. After the events of "Star Trek: First Contact" where the Borg traveled back to 2063, it's now revealed a part of the destroyed enemy ship crashed into the Antarctic. Nearly a hundred years later, an Earth research team stumbles upon the cybernetic beings and unwittingly re-activates them. After assimilating the scientists and converting a ship for their use, the newly re-awakened Borg attempt to reconnect with the Borg of this era, and it's up to Archer and Enterprise to stop them.

Invaded by the Borg, the story takes a twist when Phlox is attacked by the Borg and must develop a cure to assimilation before he becomes one of them. But with technology 200 years out of date, how can the 22nd century Enterprise hope to stop the most powerful enemy the 24th century Enterprise ever faced? Like "Star Trek: First Contact," this episode plays like a horrific zombie story, evoking a genuine sense of dread and terror as the Borg slowly re-emerge as a deadly threat.

5. Countdown (Season 3, Episode 23)

"Countdown" was the penultimate episode of Season 3, as the Xindi war barreled towards its climactic ending. Despite many within the Xindi siding with Archer and Enterprise against the attack on Earth, the Reptilians and Insectoids forge ahead with their plan to destroy the planet. In a last ditch effort to stop them from arming their ultimate weapon sphere, Archer must somehow convince the Xindi Aquatics to aid him — and the Xindi Primates — in their fight to prevent Earth's Armageddon.

The unlikely alliance heads out to meet the enemy, while Dolim and the Reptilians use a captured Hoshi Sato to help activate their doomsday weapon. In the midst of the battle, Reed and the MACOs lead a mission to retrieve Sato, with one major character making the ultimate sacrifice to complete their mission. But all hope may be lost when the Sphere Builders themselves, the mysterious race that has been guiding the Xindi all along, directly intervene to ensure that Archer fails.

4. Zero Hour (Season 3, Episode 24)

The final episode of Season 3, "Zero Hour" is the epic conclusion to the season-long Xindi War that saw a race of malevolent aliens try to wipe out all of humanity. In this final installment, it's T'Pol in command of Enterprise in the final assault on the Xindi fleet, hoping to halt the massive weapon spheres that is on a direct course for Earth. But when they arrive, they find the Sphere Builders are ready for them, with a powerful energy field protecting the network of spheres. 

Captain Archer, meanwhile, will stop at nothing to end the threat of the Xindi weapon. Entering its vortex with a plan to stall its operation, he manages to get help from an unexpected ally. In a final showdown, Enterprise's captain comes face to face with Dolim, the Reptilian leader, and only one will make it out alive. But the end of the Sphere Builder's plans isn't the end of trouble for Archer, with problems in time causing ripple effects that prove more damaging than any alien weapon.

3. Carbon Creek (Season 2, Episode 2)

"Carbon Creek" flashes back some 200 years to a rural town in Eastern Pennsylvania, circa 1957. There, a Vulcan research team has crash landed. It is led by T'Mir, the ancestor of Enterprise's science officer T'Pol. Stuck on the backwater planet, their ship cannot function, and their rescue could be months away — or longer. Against her better judgement, T'Mir accepts her fellow officer Mestral's suggestion that they get acquainted with the locals of the nearby town of Carbon Creek, as a way of getting supplies to sustain them while they wait for rescue.

But as the days drag on, the three Vulcans get more closer with the people of the town, making friends and even getting jobs, with Mestral working as a coal miner. Though T'Mir wants to keep her distance from the primitive humans in the town, Mestral grows a fondness for them. T'Mir does not approve, and is even more alarmed when Mestral reveals he has taken a human lover and wishes to stay behind and build a life on Earth. With a message of tolerance and understanding, "Carbon Creek" is an episode sure to leave you feeling hopeful for the future.

2. Azati Prime (Season 3, Episode 18)

"Azati Prime" sees Archer and Enterprise find where the Xindi are building their super weapon. Hatching a plan to infiltrate the facility and destroy it before it becomes operative, Archer knows it's a mission he will not be coming back from. But just as he's about embark on his suicide mission, time agent Daniels whisks Archer away to the future to convince him not to go through with it: history needs him alive if the United Federation of Planets is to ever become a reality and the timeline kept intact. But Archer is unconvinced that his role in history is that critical, and puts his plan into motion.

When Archer's mission goes awry and he's taken captive by Dolim — leader of the Xindi Reptilians — he must somehow convince the Xindi Primate Degra that he's not their enemy. With little more than a relic given to him by Daniels, he must prove that the information from the Sphere Builders — who've guided their entire mission — cannot be trusted.

1. Twilight (Season 3, Episode 8)

In the middle of the ongoing war with the Xindi, "Twilight" sees Captain Archer injured while saving T'Pol from a dangerous anomaly. He suffers a form of amnesia as a result. Unable to retain long term memories, Archer is removed from command, and T'Pol becomes captain of the ship. But without Archer on the bridge, Enterprise's mission to stop the Xindi and save Earth fails. The planet is destroyed, and the last remnants of humanity are scattered and listless, with T'Pol and Archer living on a remote planet where she has become his caretaker in his deteriorating condition.

But a visit from Doctor Phlox leads to a possible cure that would not only remove Archer's amnesia, but send him back to the time of the original disaster that caused it. If successful, Archer might even be able to go back to change history and save humanity. But to treat Archer, Phlox must bring him aboard Enterprise, and a sudden attack from the Xindi makes it a race against time to turn back the clock and prevent the annihilation of Earth.