Dagger of the Mind
An escaped inmate from a penal colony, who turns out to be a doctor, not a patient, prompts McCoy to demand an investigation of the facility. Kirk and psyciatrist Dr. Helen Noel beam down to the colony and discover the unethical use of brain washing machines. Dr. Adams tries to prevent Kirk and Noel from revealing his secret, but they manage to escape, and Adams is killed by his own machine.
- Dr. Tristan Adams: James Gregory
- Dr. Simon van Gelder: Morgan Woodward
- Dr. Helen Noel: Marianna Hill
- Lethe: Suzanne Wasson
The Corbomite Maneuver
The Enterprise destroys a space buoy, which draws attention of a rather large alien vessel. The alien, Balok, charges that the Enterprise is tresspassing and must be destroyed. Kirk bluffs and claims that the corbomite in the ship's hull will cause an explosion that will destroy both vessels. A small vessel takes the Enterprise in tow, and is damaged when the Enterprise tries to break free. When Kirk and McCoy beam aboard to aid the injured, they discover that there is only one alien, who was just testing to see if they were as peaceful as they claimed to be.
- Lt. Dave Bailey: Anthony Call
- Balok: Clint Howard
The Menagerie Part I and Part II
Spock kidnaps his former Captain, Christopher Pike, who has been left completely disabled by a radiation accident. He attempts to take him to a forbidden planet, Talos IV, where he can life a normal life once again, through the Talosians ability of illusion. Spock is stopped, and courtmartialed, where this is revealed along with the reasons Talos IV is forbidden. Starfleet command eventually drops the charges and allows Pike to be taken to Talos IV.
- Commadore Jose Mendez: Malachi Throne
- Captain Christopher Pike: Jeffrey Hunter
- Vina: Susan Oliver
- The Keeper: Meg Wyllie
- Number One: M> Leigh Hudec (Majel Barrett)
- Yeoman Cold: Laurel Goodwin
- Miss Piper: Julie Parrish
- Dr. Phillip Boyce: John Hoyt
The Conscience of the King
The last witnesses who could identify Kodos the Executioner are being murdered one by one. Though Kodos was presumed dead after the massacre that he authored, he was indeed alive, living a peaceful life as a Shakespearian actor. Kirk has to prove that Karidian is indeed Kodos and discover who is really killing the survivors.
- Anton Karidian: Arnold Moss
- Lenore Karidian: Barbara Anderson
- Lt. Riley: Bruce Hyde
- Lt. Leslie: Eddie Paskey
- Lt. Matson: David Troy
- Martha Leighton: Natalie Norwiick
- Dr. Thomas Leighton: William Sargent