In the mid-22nd century, the Earth ship Enterprise is launched under the command of Captain Jonathan Archer. When the crew rescues an alien from a crashed spaceship, Earth gets its first look at the alien's race - the Klingons. Archer and his crew must walk a fine line as they attempt to communicate with the Klingon pilot, whose language is completely unknown, and whose homeworld wants him back. Is this the beginning of friendship...or interstellar war?

Captain Jonathan Archer, T'Pol and Trip meet Sarin and she explains that Klaang is a courier, bringing an important message from her to the leaders of the Klingons in Kronos about rebels Suliban that intend to promote the Temporal Cold War among the Klingons. Archer feels the need of rescuing Klaang and travels to the Suliban mother-ship with Trip to bring the Klingon back to Enterprise. T'Pol seems to understand that loyalty is an emotion that cannot be avoided by humans.

Captain Archer wants to convert curiosity into deeds and decides to enter a ship floating in space. Hoshi has trouble adjusting to life on Enterprise.

Archer sends an away team to a habitable, luscious planet for observation. But when a storm occurs, the team begins to experience paranoid delusions.

After helping to repair the warp drive on board of a Xyrillian ship, Trip notices a strange bulging on his arm.

Enterprise tries to find out what happened on Terra Nova, the first colonization attempt outside Earth's solar system.

Archer, Trip and T'Pol are captured by the Andorians at a Vulcan monastery on P'Jem. They believe that the monastery is being used to spy on Andoria.

Enterprise discovers a comet which contains the very rare element eisilium. Then unexpectedly a Vulcan ship arrives. Captain Vanik tells they're interested in human behavior.

T'Pol finds unusual neutrino readings on a planet with a preindustrial society.

Enterprise is sent to help the freighter Fortunate after an attack. However, its first officer, Ryan, is hiding something.

Enterprise has a group of aliens watching a stellar phenomenon on board. When the ship is miraculously saved from blowing up, crewman Daniels has an important message for Archer.

After an attack by a mysterious ship, Archers orders Enterprise's return to Jupiter to install phase cannons; Hoshi makes plans for Malcolm's birthday.

Phlox is asked to save the Valakians from annihilation by disease. However, he discovers something unusual about the Menk, another humanoid race on the planet.

Enterprise tries to rescue a Klingon ship from sinking into a gas giant.

T'Pol is being recalled because of Enterprise's involvement in the destruction of the P'Jem sanctuary. She and Captain Archer are later kidnapped while visiting the planet Coridan.

While returning to Enterprise in Shuttlepod One, Trip and Reed see apparent evidence that the ship has been destroyed. With only days of oxygen left, they must find a way to survive long enough for rescue.

When Enterprise encounters a ship of Vulcan pilgrims, T'Pol is convinced by one of them to perform a Vulcan mind meld.

Lieutenant Reed discovers a rogue planet, which has broken out of orbit and therefore is devoid of any light. Life is still possible in some places because heat is bubbling up from under the surface, but T'Pol doesn't detect any humanoid life. Further scans however give a strange energy reading which seems to be coming from a ship on the surface. After the crew has landed, they encounter the Eska. The Eska come from another planet and they say they are hunting for the drayjin, an animal considered a delicacy. When captain Jonathan Archer tries to sleep on the planet, he hears a voice calling him by his name. A human female is wandering in the forest. Somehow he seems to know her.

Almost the entire crew is left unconscious when four Ferengi pirates raid Enterprise. A still conscious Trip is the only one who can get rid of them.

The crew of Enterprise searches for a seemingly abandoned ship on a desert planet.

Archer and Mayweather are captured by the Tandarans and placed in a Suliban internment camp.

A fibrous, web-like alien creature comes aboard the ship and several of the crew becomes entangled in it including Archer and Trip, and it seems Hoshi is the only one who can try to communicate with the creature.

Enterprise is planning a trip to the relaxation planet Risa, when it gets an urgent request from the Vulcan High Command. They must pick up ambassador V'Lar who has fallen in disgrace. Apparently she misused her position during negotiations on the planet Mazar and has been evicted. After Enterprise picked up V'Lar and is on its way for a meeting with the Vulcan warship Sh'Ran, suddenly a Mazarite ship appears. They want V'Lar for further interrogating. When captain Archer wants to discuss it first with Starfleet Command, they open fire.

Enterprise is for the second time on its way to Risa when yet again another urgent matter comes up: a distress call. It comes from a small vessel. The owner, Zobral, is extremely happy with the help from Enterprise and invites Captain Archer to his home world for a good meal and a game of Geskana. When Archer and Trip have landed on the desert planet, Enterprise gets a message from the Torothan Chancellor Trelit. He says Zobral isn't as nice a man as captain Archer thinks.

The members of the Enterprise crew are faced with various misadventures and challenges while taking a two day break from their duties on the planet of Risa.

Enterprise discovers a mining colony of the Paraagans. The crew gets an invitation for a meeting on the surface and a shuttle pod tries to break through the atmosphere. All of a sudden just under the shuttle a giant explosion begins and scorches the earth beneath. All 3600 colonists are reported dead. After examination, Enterprise finds out plasma leaking from the pod's vents ignited tetrazine in the atmosphere. Lieutenant Reed, however, ensures he closed the plasma vents before the shuttle went of. After conversations with admiral Forrest of Starfleet Command, Captain Archer learns that Enterprise's mission is canceled and they must return home, not to return to space for another ten or twenty years. When the ship has altered course, crewman Daniels, a time traveler, pays a visit to captain Archer.

Captain Archer and temporal agent Daniels have been stranded in the 31st century. In a library they investigate the damage to the time line and try to find way a to get Archer back in his own century. Meanwhile Silik the Suliban leader is trying his utmost to find the whereabouts of Archer and he is willing to go far for the answer. But the crew of Enterprise has plans of their own. Trip finds a way to use the com system and is able to speak with Reed. Together they try to contact other crew members and make plans to purge Enterprise of the Sulibans.

On the first anniversary of her assignment to Enterprise, T'Pol tells Archer and Trip about the first contact between humans and Vulcans, which involves three Vulcans becoming stranded in the town of Carbon Creek, Pennsylvania in 1957.

The safety of Enterprise rests on Reed's shoulders when the ship becomes trapped in a Romulan minefield and Romulan ships are closing in on them.

Enterprise seeks repairs from their encounters with the Romulans, where they stop at a desolate but idyllic repair station. But all is not what it seems when Mayweather is suddenly found dead.

After previously offending the Kreetassans, Enterprise attempts to make a better second impression, only to upset the alien race once again. A frustrated Captain Archer returns from the planet only to be further upset to find that his dog Porthos, has been affected by a pathogen native to the world. While Phlox works around the clock treating Porthos, Archer stands vigil in sickbay, experiencing first-hand the quirky everyday life of his Denobulan Doctor.

Enterprise visits a colony with a deuterium trading post. But the people seem to be pretty unwilling to trade. Are they hiding something?

T'Pol asks Captain Archer to join her on a mission to capture a Vulcan fugitive that escaped her years ago.

Upon returning from covertly observing a pre-warp culture, Lieutenant Reed realizes he lost his communicator somewhere on the planet. Archer and Reed return to recover the lost technology, only to find the natives found it first. Captured and interrogated, the crewmen find themselves doing even more damage to the culture, who have scanned the prisoners and know them to be of another race. Meanwhile, Tucker and Mayweather try to figure out how to activate the cloak on the Suliban cell ship so they can mount a discreet rescue.

T'Pol must save the ship after the crew becomes obsessed with trivialities during the approach to a black hole.

After Hoshi uses the transporter to avoid running into a storm, she starts to feel very strange.

While Trip is repairing a stasis pod at a Retellian cargo ship and the woman inside, heir apparent to the throne of Krios, wakes up, the ship makes a hasty departure. Trip must make a plan to escape.

After receiving a warning about a radioactive storm approaching Enterprise, the crew is forced to take shelter in the ship's catwalk.

Trip's shuttlepod is shot down by a hostile race and is forced to land on a deserted moon. There he must team up with the alien who shot him down in order to find a way back to Enterprise.

T'Pol is diagnosed with a possibly fatal neurological disease as a result of a mind meld. Meanwhile, one of Phlox's wives visits Enterprise and becomes very interested in Trip.

Captain Archer is asked to negotiate between the Andorians and Vulcans who are fighting over a small planet.

Enterprise discovers a pod with the body of a human that seems to be wanted by both Sulibans and Tholians.

Archer and Trip are accused of smuggling and sent to the penal colony Canamar. While Enterprise manages to negotiate their release, a mutiny breaks out on the prison ship.

Enterprise is held captive by non-corporeal beings who claim to be explorers.

After Enterprise lends aid to a group of accused rebels, Captain Archer faces a tribunal and charges of conspiring against the Klingon Empire.

Mayweather temporarily leaves Enterprise to visit the cargo ship Horizon, where he was born and raised. Meanwhile, the Enterprise crew observes an unusual planetary event.

At Dr. Phlox's request, Enterprise attempts to retrieve 3 Denobulan scientists from the planet Xantoras, where the Goverment has ordered all off-worlders to evacuate within 3 days. Tucker, Reed, and Mayweather navigate a series of labyrinthine underground caves in search of the scientists. Meanwhile, Enterprise lends assistance to a damaged ship fleeing the planet. Doctor Phlox faces an ethical dilemma when one of the refugees of the ship refuses life-saving treatment. The patient, an Antaran, holds a grudge against Phlox stemming from a war between their races that ended 300 years ago and would rather die than be treated by a Denobulan. Phlox defies Archer's direct order to force treatment because it goes against the Deobulan code to yield to "the will of the patient."

Enterprise encounters a hyper-giant star. While there, they make first contact with the Vissians, a technologically sophisticated race with three genders. While making quick friends, and eagerly learning about the advanced technology, Trip gets curious about the Vissians third gender, known as the Cogenitor, who is crucial in the Vissian reproductive process. Against the wishes of the Vissians, Trip befriends the Cogenitor and encourages it to defy its cultural boundaries, which the Vissians are made aware of, and are angered by.

An Arctic research team makes a startling find: cybernetic creatures - Borg - buried in the ice. When the revived aliens seize control of a spacecraft, it's up to Archer to keep them from contacting the Collective and threatening Earth.

After his close friend and colleague A.G. Robinson is killed in a mountain climbing accident, Captain Archer tells T'Pol about the Warp 2 test flight almost ten years earlier.

After exploring an uninhabited planet, Captain Archer is taken prisoner by a Tellarite bounty hunter who was hired by the Klingons to return Archer to Qo'noS.

An alien probe launches a devastating attack on Earth. Archer, still being hunted by the Klingons, brings the Enterprise back home to investigate.

Enterprise has been in the Delphic Expanse for six weeks and have yet to get any intel about the Xindi. Strange anomalies affect the ship, sending cargo flying violently through the bays, pockets of atmosphere losing gravity and other incidents defying the known laws of physics. T'Pol helps Trip's insomnia with an intimate Vulcan therapy. Archer and Trip find another race of Xindi imprisoned in a mine.

After an attack by Osaarian pirates, Enterprise follows them to a mysterious sphere.

Archer, Reed and Sato are transformed into aliens while visiting a planet.

Enterprise helps an alien woman, Rajiin, seeking to escape her life as a sex slave. Once on board she uses her alien abilities to gather biometric data about humans and is recaptured by her employers, the Xindi council.

Enterprise answers a distress signal from a stranded Vulcan ship, only when arriving they find the ship completely desolate, wrecked - and filled with Vulcan zombies.

Hoshi Sato is contacted by a 400-year-old telepathic alien exiled on planet in the Expanse, shunned by his society because of his abilities. The alien offers to use his powers to help Enterprise find the Xindi and the weapon they are building, but only if Hoshi will stay with him while he works. She agrees to stay behind, while Enterprise confirms the Expanse has a second Sphere and is on its way to investigate.

Enterprise follows a lead and discovers a Xindi lab that refines Kemocite, the key ingredient in the weapon being built to destroy Earth. An away team of Archer, Reed and Hayes confront the lead researcher, Gralik Durr, who was employed by Degra to refine the Kemocite but was never told what it would be used for. When Gralik realizes it was his research that contributed to the 7 million deaths on Earth, he agrees to help Archer prevent further loss of life. Meanwhile, on Enterprise, Phlox and Tucker study the weapon they seized from the Xindi and find an organic component, a life-form serving as the rifle's power cell. Despite T'Pol's objection, Tucker tests the weapon.

His memory crippled, Archer awakens years in the future, after the Xindi have reduced Earth to a cinder and the remnants of humanity have settled on a distant planet. Now, Archer learns that he may be the key to undoing this tragedy.

Enterprise investigates a previously unknown colony of humans who are living in the fashion of the American Old West. They are oppressing an alien race called the Skagarans.

Archer decides to make a fast-growing clone of Trip to help save his life while Enterprise is stranded in a dangerous field with nucleonic particles.

Archer and T'Pol travel back in time to Detroit in 2004 to stop three Xindi-Reptilians from constructing a bioweapon.

Enterprise is taken over by religious zealots who want to use the ship in a war against heretics.

Enterprise has found the location of the testing site of the Xindi weapon and gets some rather unexpected help.

Archer and the Xindi Degra are in a shuttle. With Degra suffering from memory loss, Archer tells him they escaped together from a prison and that the Insectoids took power after destroying Earth.

With Reed and Hayes fighting over a training program and Trip seemingly making T'Pol jealous, Enterprise discovers a dying alien in a pod with technology similar to the Spheres.

While in command of Enterprise because the entire crew is in a coma, Dr. Phlox starts hearing some strange sounds.

Captain Archer orders the crew of Enterprise to save a Xindi-Insectoid hatchery.

Archer decides he should pilot a kamikaze shuttle to destroy the Xindi weapon. Temporal agent Daniels urges him to reconsider.

Captain Archer has been returned to Enterprise by the Xindi council awaiting a hearing. But after a heavy attack by the Reptilians, Enterprise is stranded without a functional warp drive. They meet another ship in trouble because of space anomalies. The ship's captain isn't willing to trade in their warp coil and Archer must make a tough decision. Meanwhile T'Pol is having some strange sensations and can't control her emotions.

As the crew continues to repair the ship and mourn the dead, Archer works to create trust and form a partnership with members of the Xindi council.

Trying to pass through a subspace corridor, Enterprise is stopped by a version of itself from the future.

Enterprise has arrived at the location of the Xindi Council and with the help of Degra, Archer can make his plea in front of the five races of Xindi. Archer needs to prove that the Sphere Builders have been telling lies. While the Primates and Arboreals are already aware of the truth, convincing the other three races will not be easy. The Reptilians and Insectoids refuse to even listen to Archer. Meanwhile, the Sphere Builders haven't been sitting still, and have arranged a secret meeting with the Reptilians.

While the Reptilians force Hoshi to decipher a launch code, the Primates, Arboreals and Archer think of a way to stop the Xindi weapon.

Archer takes Degra's ship to try to prevent Earth from being destroyed and gets some unexpected help. Enterprise tries to destroy Sphere 41, but the Sphere Builders know about the plan.

Following the destruction of the Xindi weapon, the Enterprise crew discovers that they have been sent back in time to 1944. However, history has been altered, leaving Nazi Germany in control of a large portion of the eastern United States.

After Silik attacks Trip, Vosk wants to make a deal with Archer: supplies of the ship for the completion of his time machine in return for a trip to the 22nd Century.

The crew take some time off. Archer meets an old friend, Captain Erika Hernandez. T'Pol takes Trip to Vulcan, with a surprise waiting. Phlox finds out Earth has become xenophobic.

After a Klingon ship is attacked, it's discovered the imprisoned Dr. Soong's genetically enhanced humans are responsible. Archer takes him to prevent a war.

The Augments are on their way to Cold Station 12, where Augments embryos are kept.

The Augments have yet again escaped. While Dr. Soong wants to hide the embryos, Malik has an entirely different and way more cruel plan.

After a bombing destroyed the Earth embassy on Vulcan, a group known as the Syrrannites are suspected. T'Pol receives a map from her Syrrannite mother, leading into a dangerous desert, the Forge.

T'Pol and Archer confront the Syrrannites and meet T'Pau who denies the embassy bombing. Archer, who has Surak's essence, is asked to help. V'Las threatens Enterprise to make sure an attack on the Syrrannites isn't witnessed.

While Enterprise travels to Andoria to warn them of the attack, Archer tries to bring the Kir'Shara to the High Command.

Dr. Emory Erickson comes aboard to supposedly conduct tests for subquantum transportation. However, he seems to have a different agenda.

Noncorporeal aliens inhabit the bodies of Enterprise crew members to study how the crew reacts to a lethal virus infection that has afflicted Trip and Hoshi.

Enterprise escorts Tellarites to peace talks with Andorians. While transporting they rescue Andorians and say the Tellarites attacked them. Enterprise is soon attacked by an Andorian ship, and Archer must prove who is responsible.

Captain Archer must convince Vulcans, Tellarites and Andorians to unite to find the Romulan ship.

Enterprise finds out the marauder was piloted telepathically by an Aenar, a subspecies from Andoria.

While Enterprise is visiting Earth, Phlox is abducted by the Klingons and forced to research a cure for a virus destined to wipe out the race. Reed is tapped by a secret agency and ordered to betray Archer. Trip transfers to the Columbia.

While Enterprise tries to bring Trip on board to reverse the malicious Klingon modifications, Phlox and Antaak find a cure for the virus that will not please General K'Vagh.

The men of Enterprise fall under the seductive control of three Orion women. Trip is the only male member of the crew not to succumb to the women.

Set in the dark and oppressive Mirror Universe, Commander Archer leads a mutiny in a bold attempt to seize control of an advanced starship - a vessel from the future that may be the key to saving the Terran Empire.

The Mirror Universe saga concludes as Archer declares himself captain of a formidable starship from the future, while his alien crew launch a rebellion in a desperate bid to keep him from achieving ultimate power.

While attending a conference on a proposed interplanetary alliance, Trip and T'Pol find out from a dying woman that they have a baby. Investigation shows the woman was a member of the xenophobic organization Terra Prime.

Paxton threatens to destroy Starfleet Headquarters if all aliens don't leave Earth. Enterprise must shut down the verteron array on Mars, but it is extremely well defended.

In 2370, Commander William T. Riker is trying to clear his mind and relives the last mission of the first Enterprise on the holodeck.

After Enterprise lends aid to a group of accused rebels, Captain Archer faces a tribunal and charges of conspiring against the Klingon Empire.

Archer and the Xindi Degra are in a shuttle. With Degra suffering from memory loss, Archer tells him they escaped together from a prison and that the Insectoids took power after destroying Earth.

Enterprise discovers a mining colony of the Paraagans. The crew gets an invitation for a meeting on the surface and a shuttle pod tries to break through the atmosphere. All of a sudden just under the shuttle a giant explosion begins and scorches the earth beneath. All 3600 colonists are reported dead. After examination, Enterprise finds out plasma leaking from the pod's vents ignited tetrazine in the atmosphere. Lieutenant Reed, however, ensures he closed the plasma vents before the shuttle went of. After conversations with admiral Forrest of Starfleet Command, Captain Archer learns that Enterprise's mission is canceled and they must return home, not to return to space for another ten or twenty years. When the ship has altered course, crewman Daniels, a time traveler, pays a visit to captain Archer.

Captain Archer is asked to negotiate between the Andorians and Vulcans who are fighting over a small planet.

Enterprise investigates a previously unknown colony of humans who are living in the fashion of the American Old West. They are oppressing an alien race called the Skagarans.

Archer and Trip are accused of smuggling and sent to the penal colony Canamar. While Enterprise manages to negotiate their release, a mutiny breaks out on the prison ship.

The Augments have yet again escaped. While Dr. Soong wants to hide the embryos, Malik has an entirely different and way more cruel plan.

Enterprise follows a lead and discovers a Xindi lab that refines Kemocite, the key ingredient in the weapon being built to destroy Earth. An away team of Archer, Reed and Hayes confront the lead researcher, Gralik Durr, who was employed by Degra to refine the Kemocite but was never told what it would be used for. When Gralik realizes it was his research that contributed to the 7 million deaths on Earth, he agrees to help Archer prevent further loss of life. Meanwhile, on Enterprise, Phlox and Tucker study the weapon they seized from the Xindi and find an organic component, a life-form serving as the rifle's power cell. Despite T'Pol's objection, Tucker tests the weapon.

Lieutenant Reed discovers a rogue planet, which has broken out of orbit and therefore is devoid of any light. Life is still possible in some places because heat is bubbling up from under the surface, but T'Pol doesn't detect any humanoid life. Further scans however give a strange energy reading which seems to be coming from a ship on the surface. After the crew has landed, they encounter the Eska. The Eska come from another planet and they say they are hunting for the drayjin, an animal considered a delicacy. When captain Jonathan Archer tries to sleep on the planet, he hears a voice calling him by his name. A human female is wandering in the forest. Somehow he seems to know her.

Enterprise escorts Tellarites to peace talks with Andorians. While transporting they rescue Andorians and say the Tellarites attacked them. Enterprise is soon attacked by an Andorian ship, and Archer must prove who is responsible.