Charlie X

1966-09-15

Raised from boyhood by non-corporeal beings, 17 year old Charles Evans is picked up and transferred to the Enterprise. On board the ship, the teenager proves dangerously unable to wield his enormous psionic powers with maturity.

Where No Man Has Gone Before

1966-09-22

When Enterprise encounters a Force Field at the edge of the Galaxy, one of the crew members psionic abilities are accelerated to God like proportions causing him to become a powerful murderous being.

The Naked Time

1966-09-29

An alien virus strips the enterprise crew of their inhibitions, causing chaos as each crew member is overcome by hidden emotions. Meanwhile, the Enterprise is being pulled inexorably into a nearby planet's gravity well.

The Enemy Within

1966-10-06

Split by a transporter malfunction into two beings with very different personalities, the resulting twin Captain Kirk proves that neither a purely evil nor a sweetly good captain can survive without the missing half.

Mudd's Women

1966-10-13

Rescuing the crew of a ship from an asteroid belt, the Enterprise plays host to conman extraordinaire, the cunning Harry Mudd and his cargo: three beautiful women looking for suitors.

What Are Little Girls Made Of?

1966-10-20

Helping nurse Christine Chapel search for her fiancé, the Enterprise finds a detached Dr. Korby working on a plan to create Android duplicates of key figures, beginning with James Kirk.

Miri

1966-10-27

On a planet populated by children whose aging process has been slowed artificially. Kirk’s landing party members contract a virus that kills adults. Despite their violent attacks, Kirk is determined to help the children.

Dagger of the Mind

1966-11-03

When a wild eyed maniac escaping from the Tantalus Penal Colony turns out to be one of the psychiatric staff, Kirk investigates the institution and discovers a chilling exercise in mind control.

The Corbomite Maneuver

1966-11-10

Threatened by the sinister captain of a powerful alien vessel, Kirk claims that the Enterprise carries a powerful explosive which will destroy both ships. The move produces unexpected actions from the alien adversary.

The Menagerie (1)

1966-11-17

Apparently summoned to Star Base 11, Kirk, Spock and McCoy visit a former Enterprise Commander, the paralyzed and horribly disfigured Christopher Pike. Uncharacteristically, Spock commandeers the Enterprise, then turns himself in for court martial.

The Menagerie (2)

1966-11-24

Spock's court martial reveals the actions of Captain Pike on his previous visit to Talos IV, where the powerful Talosians tried to persuade Pike to breed with women provided for the purpose.

The Conscience of the King

1966-12-08

Contacted by one of the other two witnesses to the crimes of mass murderer “Kodos the Executioner,” Kirk is persuaded that the criminal may be disguising himself as an actor in a traveling theatrical troupe.

Balance of Terror

1966-12-15

Despite the earlier Romulan war, the Romulans have never been seen in person. The Enterprise, in pursuit of a Romulan aggressor, makes a discovery that causes suspicion about a senior crew member.

Shore Leave

1966-12-29

When McCoy sees the White Rabbit from Alice in Wonderland, the crew begins to realize that the planet they are visiting seems to have the dangerous power to turn any thought into reality.

The Galileo Seven

1967-01-05

Crash landing on a planet populated by hostile giants, the 7-man crew of the shuttlecraft Galileo find themselves unable to communicate with the enterprise or to escape the planet's atmosphere.

The Squire of Gothos

1967-01-12

Encountering an uncharted planet in an empty region of space, Kirk and his crew are entertained by Trelane, a playful being who lacks the self-control to wield his great psionic powers with discipline.

Arena

1967-01-19

With both their ships held captive by powerful beings, Kirk and the captain of the alien vessel are placed on an asteroid to fight for their lives and the lives of their crews.

Tomorrow Is Yesterday

1967-01-26

In a freak accident the Enterprise is sent back to 20th century Earth, and must find their way back without changing history.

Court Martial

1967-02-02

Captain Kirk's career is at stake when he is put on trial for the loss of a crewman during an ion storm.

The Return of the Archons

1967-02-09

The Enterprise encounters a seemingly peaceful civilization run by a "benevolent" being named Landru... who intends for them to join his people.

Space Seed

1967-02-16

The Enterprise picks up a crew of genetic supermen from the 20th century... and their leader, Khan, plans to create a new empire.

A Taste of Armageddon

1967-02-23

The Enterprise arrives at a planet to establish diplomatic relations and finds itself in the middle of a "peaceful" war that threatens to destroy the ship.

This Side of Paradise

1967-03-02

The Enterprise crew try to rescue colonists from deadly radiation, but instead encounter strange alien spores that seem to offer paradise.

The Devil in the Dark

1967-03-09

Kirk investigates a series of grisly murders on a mining planet that are the work of a seemingly hostile alien creature.

Errand of Mercy

1967-03-23

The Federation and the Klingon Empire teeter on the brink of war as Kirk investigates Organia, a humble planet, inhabited by pacifists, that is unwittingly caught in the middle.

The Alternative Factor

1967-03-30

Kirk and Spock encounter an alien named Lazarus who claims to be from an anti-matter universe.

The City on the Edge of Forever

1967-04-06

Kirk and Spock must travel into the past in order to correct a change that will alter history.

Operation: Annihilate!

1967-04-13

Kirk and the Enterprise must combat parasitic aliens threatening the lives of millions.