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

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.

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.

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.

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 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.

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.