While on Pyris VII, the crew discovers a haunted castle and a black cat. The Enterprise is held hostage and McCoy, Sulu, and Scotty are turned into zombies. Written by: Robert Bloch. Directed by: Joseph Pevney.
Transporting Commissioner Nancy Hedford to the Enterprise for Medical treatment, the shuttle carrying her is forced to crash land on a planet by a mysterious cloud creature, who will not let them leave. On the planet, they find a young Zefram Cochrane, the discoverer of the space warp, who supposedly died over a hundred years ago at the age of 87. Kirk must find a way to get off the planet and back to the ship before the commissioner dies. We become witness to Cochrane's test warp flight in the movie Star Trek: First Contact". Written by: Gene L. Coon. Directed by: Ralph Senesky.
The Enterprise journeys to Capella IV to set up trade relations with the inhabitants before the Klingons do. However, when they find the Klingons already there, things start to go awry and the High Tier Akaar dies, condemning his wife, Eleen, and unborn son to die as well. To prevent this, Kirk and party flee to the mountains with Akaar's wife. While Kirk and Spock prepare for battle, McCoy must persuade Eleen to love her unborn child. Written by: D. C. Fontana. Directed by: Joseph Pevney.
In the vicinity of Pollux IV, a large green hand of pure energy stops the Enterprise. And the Greek god Apollo invites Kirk to beam down. Apollo tries to romance Lt. Carolyn Palamas, who Scotty has already fallen for. Written by: Gilbert Ralston. Directed by: Marc Daniels.
Spock starts to behave quite oddly and irrationally, and requests a leave of absence, which because of timing Kirk refuses. Regardless and not realizing it, Spock orders a course change to Vulcan without Kirk's consent. When McCoy discovers Spock is dying, Kirk orders a course for Vulcan for Spock's prearranged marriage and wedding, where Kirk ends up in a fight against Spock to the death. Written by: Theodore Sturgeon. Directed by: Joseph Pevney.
Investigating the destruction of several star systems, the Enterprise stumbles upon a crippled USS Constellation. Aboard, they find only the ship's commander, Commodore Matthew Decker, who beams back to the Enterprise and takcommand, while Kirk continues trying to restore power to the Constellation, when a giant planet killer comes back and Decker uses the Enterprise to attack before taking his own life by flying a shuttle into it. Written by: Norman Spinrad. Directed by: Marc Daniels.
On therapeutic leave on Argelius II, Scotty is the only possible suspect in a series of brutal murders of young women. In two of the three murders, Scotty blacked out and doesn't remember anything, and in the third one he felt something push him out of the way. A hearing is convened aboard the Enterprise to prove Scotty's innocence and find the real murderer. Written by: Robert Bloch. Directed by: Joseph Pevney.
The ship is attacked by a probe of unknown origin that almost destroys it. It stops its attack when it hears Kirk's name over communications. The probe, Nomad, turns out to an Earth probe launched in 2020. It's programming has been significantly altered and it even kills Scotty and erases Uhura's mind. Written by: John Meredyth Lucas. Directed by: Marc Daniels.
The Enterprise discovers what at first seems to be a paradise but actually has plants that shoot poisonous darts, clay that explodes on impact when thrown, highly acidic rain, and culture that seems to have never progressed, has no idea what children are, and bows to a god that actually turns out to be a computer. Written by: Max Ehrlich. Directed by: Joseph Pevney.
After trying to establish diplomatic relations with the peaceful Halkan Council, the landing party, including Kirk, McCoy, Scotty, and Uhura, beams into an alternate universe where Spock has a beard and one advances in rank by assassination. The repercussions of Kirk's interference in the mirror universe can be seen in DS9 #443 "Crossover". Written by: Jerome Bixby. Directed by: Marc Daniels.
On beaming down to Gamma Hydra IV, the crew finds a couple in their twenties who look like they're in their nineties. Soon the entire landing party, with the exception of Chekov begins to age rapidly. Soon the highest ranking officer, who has no command experience, is forced to pass through the edge of the Romulan neutral zone. Watch for Kirk's use of The Corbomite Maneuver (ep #3). Written by: David P. Harmon. Directed by: Joseph Pevney.
An Enterprise crewman who turns out to be an android, locks the ship on course for an unknown planet where old friend criminal Harry Mudd has been living among a population of androids. Mudd arranged for the androids to bring a ship so he could get off the planet and strand the crew, little does he know the androids intend on stranding him there as well. Written by: Stephen Kandel. Directed by: Marc Daniels.
The Enterprise is diverted to space station K-7 to protect a shipment of quadrotriticale. Also in the neighborhood is a Klingon battle cruiser, wanting some R&R. But what causes the real trouble are little furry creatures called tribbles. Klingon Commander Koloth is later seen in DS9 #439 "Blood Oath". This episode provides the basis for DS9 #503 "Trials And Tribble-ations". Written by: David Gerrold. Directed by: Joseph Pevney.
After discovering the wreckage of the SS Beagle, the crew is led to an Earth-like planet in the equivalent of the 1960s, only the Roman civilization never fell in its history. Here they learn that the Beagle's Captain, R. M. Merik, has violated the prime directive and has interfered in the society. Written by: Gene Roddenberry & Gene L. Coon. Directed by: Ralph Senesky.
The Enterprise picks up Spock's parents on Vulcan to carry them and others to a diplomatic conference of Babel. While en route, one of diplomats is murdered and Spock's father Sarek is the prime suspect. Sarek is also ill and only Spock can save him. Written by: D. C. Fontana. Directed by: Joseph Pevney.
While visiting a once peaceful planet, Spock suffers a nearly fatal gunshot wound and Kirk suffers a deadly bite from a Mugatu but is saved by a friend he knew with the hill people from a previous visit. As it turns out, the valley people are being supplied with guns from the Klingons. Teleplay by: Gene Roddenberry. Story by: Jud Crucis. Directed by: Marc Daniels.
As Kirk, Uhura, and Chekov prepare to beam down for a routine survey mission. They are instantly transported across the galaxy where they are treated as slaves and must to fight to amuse their captors. Written by: Margaret Armen. Directed by: Gene Nelson.
While on a mission to extract a rare mineral, Kirk smells a cloud creature which eleven years ago, when Kirk was young lieutenant, killed half the crew of the Farragut. Back then Kirk was unable to kill it, because he delayed firing. Now Kirk with a guilt and revenge-filled obsession, at the risk of his crew, is going after it to destroy it. Written by: Art Wallace. Directed by: Ralph Senesky.
The Enterprise is sent to learn the fate of the USS Intrepid, a starship manned entirely by Vulcans. Where an entire system used to exist, there is now a black void in space, where the laws of physics are reversed. At the centre of this void is a giant ameba several hundred times the size of the Enterprise. Written by: Robert Sabaroff. Directed by: Joseph Pevney.
On a mission to learn the fate of USS Horizon 100 years before, the Enterprise comes to Iotia where they find an entire civilization centred around a book, Chicago Mobs of the Twenties published in 1992, left by the Horizon. Can Kirk fix the damage done by "the book" while being kidnapped, put on ice, and trying to drive a stick shift to make a hit? Teleplay by: David P. Harmon & Gene L. Coon. Story by: David P. Harmon. Directed by: James Komack.
On beaming down to answer a distress call, Kirk and party are held captive by a group from the Andromeda Galaxy who then move to take over the Enterprise and reduce non-essential crew members to small blocks to prepare for the 300-year journey back to their home planet. Teleplay by: D. C. Fontana & Jerome Bixby. Story by: Jerome Bixby. Directed by: Marc Daniels.
The crew stumbles upon three surviving on a planet long since dead, who request to use bodies of the crew so they can make android bodies for themselves. But one of them decides to keep Spock's body for himself. Written by: Gene Roddenberry. Directed by: Ralph Senesky.
Arriving at Ekos to learn the fate of Federation cultural observer John Gill, the Enterprise is fired upon by atomic missiles. On beaming down they discover a Nazi-like civilization with John Gill as the Freuer. The Nazi Ekosians are apparently at war with neighboring planet Zeon, who have an underground movement on Ekos. Written by: John Meredyth Lucas. Directed by: Vincent McEveety.
The Enterprise is selected to test the M5 computer, which is supposed to be able to run a starship without anyone on board at all. Only the M5 has it's own mind and begins using real weapons in the test instead of simulated ones. Teleplay by: D. C. Fontana. Story by: Laurence N. Wolfe. Directed by: John Meredyth Lucas.
Upon beaming down to learn the fate of the crew of the Exeter, the landing party learns from the Exeter's Captain Ron Tracey that if they leave Omega IV's surface, they will die. Their alternative is to live eternally on Omega IV, living with the Kohms (Communists) and hiding from the Yangs (Yankees). Written by: Gene Roddenberry. Directed by: Vincent McEveety.
In a time-travel expedition back to 1968 to discover how Earth managed to avoid destroying itself, the ship intercepts a transporter beam from another part of the galaxy carrying a Gary Seven. Gary has apparently been sent to stop the launch of an orbital atomic bomb. Teleplay by: Art Wallace. Story by: Gene Roddenberry & Art Wallace. Directed by: Marc Daniels.