Enterprise, Earths first vessel capable of exploring the universe, is to embark on a dangerous first mission: bringing back a chased Klingon to his home world.
Archer learns from the Suliban Sarin that Klaang was carrying a message to the Klingons to prevent civil war in the Klingon Empire. She urges to find him.
Human curiosity speaks louder than Vulcan logic. Despite T'Pol's objection, Archer sends an away team to explore an uninhabited planet before getting a full scan of its unique properties. When nightfall arrives, the away team seeks shelter from a storm in a nearby cave. Panic and anxiety strike the team when a pollen brings on hallucinations of a life-form in the cave. Tucker's preconceptions of Vulcans are intensified when his delusions convince him T'Pol, in league with the "rock people," intend to kill him and his human crew-mates.
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.
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.
T'Pol is being recalled because of Enterprise' involvement in the destruction of the P'Jem sanctuary. Then T'Pol and Archer get kidnapped visiting the planet Coridan.
Tucker and Reed return in Shuttlepod One to rendez-vous with Enterprise, only to find evidence that it has been destroyed. An unknown phenomenon, resembling a myth known as a "micro-singularity," damages the shuttlepod, leaving the men only days of breathable air and no way to call for help.
Enterprise is on its way to explore the giant Arachnid Nebula when they rendezvous with a Vulcan ship that has been in space for more than eight years. Its crew is V'tosh ka'tur. That means they have a different interpretation of the teachings of Surak and try to find a balance between logic and emotion instead of suppressing them. Trip starts working on repairs with engineer Kov while captain Archer receives a message from the terminally ill father of Kov. Meanwhile another Vulcan, Tolaris, tries to convert T'Pol to their ways. He wants to do a mind meld with her.
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, ...
Four greedy Ferengis have invaded Enterprise while the crew is unconscious. They have already confiscated numerous valuable supplies, but are still interested in more. They wake up captain Archer to get the know the whereabouts of 'the vault'. Another crew member is still awake in the decontamination chamber, Trip. He wakes T'Pol. Since the weakness of the invaders is not difficult to find, the three try to outsmart the Ferengis.
The crew of Enterprise have a meeting with the trader D'Marr. Unfortunately he is unable to provide them with valuable ores, but knows of a location where these can be obtained. He tells he found an apparently abandoned ship and tried to empty it to make a fortune. But according to D'Marr the ship is haunted and he was forced to leave. Enterprise starts looking for the ship anyway. Scans show there really aren't any bio-signs, but after coming on board the crew soon gets the feeling they are not alone.
Captain Archer and Mayweather are investigating a strange energy reading from the other side of a moon. The next moment they find themselves in a complex inhabited by Sulibans. The Sulibans are kept against their will by the Tandarans, who are in war with the Cabal, a Suliban terrorist organization. Archer and Mayweather are held prisoner because of trespassing, but Tandaran colonel Grat assures their release will only be a formality. While captain Archer is suspicious of the Suliban at first, he soon finds out they're innocent and makes plan to release them. ...
A group of Kreetassans are on board of Enterprise for a friendly meeting. But they leave rather unexpectedly as they seem very offended by something. The crew have no idea what however. But as their ship leaves an alien gel like creature manages to crawl aboard. The creature is growing and growing and shows rather hostile tendencies as it encapsulates five crew members, including captain Archer and commander Tucker. T'Pol, Hoshi and Reed have to come up with a solution quickly. The lives of the five are at stake as the creature begins a symbiotic relationship that in ...
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 tells Zobral isn't as nice a man as captain Archer thinks.
After several delays, the Enterprise crew gets some well-deserved shore leave on the famed pleasure planet Risa. Commander Tucker and Lieutenant Reed eagerly seek out female companionship, only to fall into a tourist trap. Captain Archer meets and attractive female who seems to be more interested in his knowledge of the Suliban than his companionship. Hoshi Sato meets a fellow vacationer and they share more than eachothers' native languages. Doctor Phlox takes the opportunity to hibernate, only to be rudely awakened when Mayweather needs medical treatment.
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 the 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...