# List of Star Trek: The Original Series episodes

Created by Gene Roddenberry, the science fiction television series Star Trek (which eventually acquired the retronym Star Trek: The Original Series) starred William Shatner as Captain James T. Kirk, Leonard Nimoy as Mr. Spock, and DeForest Kelley as Dr. Leonard "Bones" McCoy aboard the fictional Federation starship USS Enterprise. The series originally aired from September 1966 through June 1969 on NBC.
This is the first television series in the Star Trek franchise, and comprises 79 regular episodes over the series' three seasons, along with the series' original pilot episode, "The Cage". The episodes are listed in order by original air date, which match the episode order in each season's original, remastered, and Blu-ray DVD box sets. The original, single-disc DVD releases placed the episodes by production order, with "The Cage" on the final disc.
After the series' cancellation, Paramount Television released Star Trek to television stations as a syndication package, where the series' popularity grew to become a "major phenomenon within popular culture". This popularity would eventually lead to the expansion of the Star Trek catalog, which as of 2020 includes nine more television series and thirteen Trek motion pictures.
In 2006, CBS Paramount Domestic Television (now CBS Television Distribution) announced that each Original Series episode would be re-syndicated in high definition after undergoing digital remastering, including both new and enhanced visual effects. (To date, the remastered episodes have only been broadcast in standard definition, though all three seasons are now available on the high-definition Blu-ray Disc format.) The remastered episodes began with "Balance of Terror" (along with, in some markets, "Miri") during the weekend of September 16, 2006, and ended with "The Cage", which aired during the weekend of May 2, 2009. The remastered air dates listed below are based on the weekend each episode aired in syndication.

## Series overview

| Season | Episodes | Episodes | Originally released | Originally released |
| Season | Episodes | Episodes | First released | Last released |
| 1 | 29 | 29 | September 8, 1966 (1966-09-08) | April 13, 1967 (1967-04-13) |
| 2 | 26 | 26 | September 15, 1967 (1967-09-15) | March 29, 1968 (1968-03-29) |
| 3 | 24 | 24 | September 20, 1968 (1968-09-20) | June 3, 1969 (1969-06-03) |

## Episodes
### Pilots (1964–65)

Star Trek's pilot episode, "The Cage", was completed between November 1964 and January 1965, and starred Jeffrey Hunter as Captain Christopher Pike, Majel Barrett as Number One, and Leonard Nimoy as Spock. The pilot was rejected by NBC as being "too cerebral" among other complaints. Jeffrey Hunter chose to withdraw from the role of Pike when creator Gene Roddenberry was asked to produce a second pilot episode "Where No Man Has Gone Before". A slightly edited version with the same title aired in 1966 as the third episode of the new series.
"The Cage" never aired during Star Trek's original run. It was presented by Roddenberry as a black-and-white workprint at various science fiction conventions over the years after Star Trek's cancellation but was not released on home video until 1986 when Paramount Home Video produced a "restored" release of "The Cage" (a combination of the original black-and-white footage and color portions of the Season 1 episode "The Menagerie") along with an introduction by Gene Roddenberry.
On October 15, 1988, Paramount Pictures aired a two-hour television special, hosted by Patrick Stewart, called The Star Trek Saga: From One Generation to the Next, which featured, for the first time, a full-color television presentation of "The Cage". In the United States, "The Cage" was released to DVD in December 2001. It was later included on the final disc in both the original and "remastered" season 3 DVD box sets listed with its original air date of October 15, 1988.
"Where No Man Has Gone Before" in its original form (production number 02a) had been forwarded to NBC, but only a re-edited version was aired, not as a pilot but as the third episode of the series (production number 02b). The original version was thought to be lost, but later appeared on bootleg VHS tapes at conventions, until a print of it was discovered in 2009 and subsequently released on home video under the title "Where No Fan Has Gone Before" - The Restored, Unaired Alternate Pilot Episode as part of the TOS season 3 box set on Blu-ray; it has not been released on DVD.
| Title | Directed by | Written by | Original release date | Prod. code |
| "The Cage" | Robert Butler | Gene Roddenberry | October 4, 1988 (1988-10-04) | 01 |
| The crew of the Enterprise follow a distress signal to the planet Talos IV, where Captain Pike is taken captive by a group of telepathic aliens who create realistic illusions. The events of this pilot are revisited in the two-part Season 1 episode "The Menagerie". |||||
| "Where No Man Has Gone Before" (pilot version) | James Goldstone | Samuel A. Peeples | - | 02a |
| After the Enterprise attempts to cross the Great Barrier at the edge of the galaxy, crew members Gary Mitchell and Elizabeth Dehner develop "godlike" psychic powers which threaten the safety of the crew and of humanity itself. Note: A re-edited version of the episode was aired as the third episode of the first season. |||||

### Season 1 (1966–67)

After Roddenberry's second pilot episode, "Where No Man Has Gone Before", received a more favorable response from NBC, Star Trek finally aired its first episode—"The Man Trap"—at 8:30PM on September 8, 1966. "Where No Man...", which eventually aired in a re-edited format as the series' third episode, retained only Spock as a character from "The Cage" but introduced William Shatner as Captain James T. Kirk, James Doohan as chief engineer Scotty, and George Takei as physicist (later helmsman) Sulu. Also joining the cast were DeForest Kelley as ship's surgeon Dr. Leonard "Bones" McCoy and Nichelle Nichols as the communications officer Uhura in "The Man Trap", the first aired episode of the series.
Although her character of Number One was not retained from "The Cage", Majel Barrett returned to the series as a new character, nurse Christine Chapel, and made her first of many recurring appearances in "The Naked Time". Grace Lee Whitney appeared in eight episodes as yeoman Janice Rand, beginning with "The Man Trap". Whitney left the series after "The Conscience of the King", but would later make minor appearances in the first, third, fourth, and sixth Star Trek films as well as one episode of the companion series Star Trek: Voyager.
Star Trek's first season comprised 29 episodes, including the two-part episode "The Menagerie", which includes almost all of the footage from the original pilot, "The Cage". Other notable episodes include "Balance of Terror", which introduces the Romulans; "Space Seed", which introduces Khan Noonien Singh and serves as the basis for Star Trek II: The Wrath of Khan; "Errand of Mercy", in which the Klingons make their first appearance; and the critically acclaimed, Hugo-Award-winning episode "The City on the Edge of Forever", which features Kirk, Spock, and McCoy traveling into the past through the Guardian of Forever.
| No. overall | No. in season | Title | Directed by | Written by | Original release date | Prod. code | U.S. households (in millions) |
| 1 | 1 | "The Man Trap" | Marc Daniels | George Clayton Johnson | September 8, 1966 (1966-09-08) | 06 | 11.36 |
| 2 | 2 | "Charlie X" | Lawrence Dobkin | Story by : Gene Roddenberry Teleplay by : D. C. Fontana | September 15, 1966 (1966-09-15) | 08 | 10.10 |
| 3 | 3 | "Where No Man Has Gone Before" | James Goldstone | Samuel A. Peeples | September 22, 1966 (1966-09-22) | 02b | 10.38 |
| 4 | 4 | "The Naked Time" | Marc Daniels | John D. F. Black | September 29, 1966 (1966-09-29) | 07 | 10.05 |
| 5 | 5 | "The Enemy Within" | Leo Penn | Richard Matheson | October 6, 1966 (1966-10-06) | 05 | 9.06 |
| 6 | 6 | "Mudd's Women" | Harvey Hart | Story by : Gene Roddenberry Teleplay by : Stephen Kandel | October 13, 1966 (1966-10-13) | 04 | 9.83 |
| 7 | 7 | "What Are Little Girls Made Of?" | James Goldstone | Robert Bloch | October 20, 1966 (1966-10-20) | 10 | 9.39 |
| 8 | 8 | "Miri" | Vincent McEveety | Adrian Spies | October 27, 1966 (1966-10-27) | 12 | 8.95 |
| 9 | 9 | "Dagger of the Mind" | Vincent McEveety | Shimon Wincelberg | November 3, 1966 (1966-11-03) | 11 | 9.94 |
| 10 | 10 | "The Corbomite Maneuver" | Joseph Sargent | Jerry Sohl | November 10, 1966 (1966-11-10) | 03 | 9.55 |
| 11 | 11 | "The Menagerie" | Marc Daniels | Gene Roddenberry | November 17, 1966 (1966-11-17) | 16 | 9.50 |
| 12 | 12 | "The Menagerie" | Robert Butler | Gene Roddenberry | November 24, 1966 (1966-11-24) | 16 | 10.21 |
| 13 | 13 | "The Conscience of the King" | Gerd Oswald | Barry Trivers | December 8, 1966 (1966-12-08) | 13 | 8.62 |
| 14 | 14 | "Balance of Terror" | Vincent McEveety | Paul Schneider | December 15, 1966 (1966-12-15) | 09 | 8.51 |
| 15 | 15 | "Shore Leave" | Robert Sparr | Theodore Sturgeon | December 29, 1966 (1966-12-29) | 17 | 10.10 |
| 16 | 16 | "The Galileo Seven" | Robert Gist | Story by : Oliver Crawford Teleplay by : Oliver Crawford and Shimon Wincelberg | January 5, 1967 (1967-01-05) | 14 | 8.89 |
| 17 | 17 | "The Squire of Gothos" | Don McDougall | Paul Schneider | January 12, 1967 (1967-01-12) | 18 | 10.82 |
| 18 | 18 | "Arena" | Joseph Pevney | Story by : Fredric Brown Teleplay by : Gene L. Coon | January 19, 1967 (1967-01-19) | 19 | 10.54 |
| 19 | 19 | "Tomorrow Is Yesterday" | Michael O'Herlihy | D. C. Fontana | January 26, 1967 (1967-01-26) | 21 | 10.98 |
| 20 | 20 | "Court Martial" | Marc Daniels | Story by : Don M. Mankiewicz Teleplay by : Don M. Mankiewicz and Steven W. Carabatsos | February 2, 1967 (1967-02-02) | 15 | 10.05 |
| 21 | 21 | "The Return of the Archons" | Joseph Pevney | Story by : Gene Roddenberry Teleplay by : Boris Sobelman | February 9, 1967 (1967-02-09) | 22 | 10.93 |
| 22 | 22 | "Space Seed" | Marc Daniels | Story by : Carey Wilber Teleplay by : Gene L. Coon and Carey Wilber | February 16, 1967 (1967-02-16) | 24 | 9.94 |
| 23 | 23 | "A Taste of Armageddon" | Joseph Pevney | Story by : Robert Hamner Teleplay by : Robert Hamner and Gene L. Coon | February 23, 1967 (1967-02-23) | 23 | 10.98 |
| 24 | 24 | "This Side of Paradise" | Ralph Senensky | Story by : Jerry Sohl and D. C. Fontana Teleplay by : D. C. Fontana | March 2, 1967 (1967-03-02) | 25 | 10.10 |
| 25 | 25 | "The Devil in the Dark" | Joseph Pevney | Gene L. Coon | March 9, 1967 (1967-03-09) | 26 | 10.38 |
| 26 | 26 | "Errand of Mercy" | John Newland | Gene L. Coon | March 23, 1967 (1967-03-23) | 27 | 9.50 |
| 27 | 27 | "The Alternative Factor" | Gerd Oswald | Don Ingalls | March 30, 1967 (1967-03-30) | 20 | 9.33 |
| 28 | 28 | "The City on the Edge of Forever" | Joseph Pevney | Harlan Ellison | April 6, 1967 (1967-04-06) | 28 | 9.39 |
| 29 | 29 | "Operation -- Annihilate!" | Herschel Daugherty | Steven W. Carabatsos | April 13, 1967 (1967-04-13) | 29 | 9.72 |
* 1 2 Credited as S. Bar-David
* ↑ Credited as Nathan Butler

### Season 2 (1967–68)

The show's 26-episode second season began in September 1967 with "Amok Time", which introduced actor Walter Koenig as Russian navigator Pavel Chekov, and granted viewers the first glimpse of Spock's homeworld, Vulcan. The season also includes such notable episodes as "Mirror, Mirror", which introduces the evil "mirror universe"; "Journey to Babel", featuring the introduction of Spock's parents Sarek and Amanda; and the light-hearted "The Trouble with Tribbles", which would later be revisited in a 1973 episode of Star Trek: The Animated Series and a 1996 episode of Star Trek: Deep Space Nine. The season ended with "Assignment: Earth", an attempt to launch a spin-off television series set in the 1960s.
| No. overall | No. in season | Title | Directed by | Written by | Original release date | Prod. code | U.S. households (in millions) |
| 30 | 1 | "Amok Time" | Joseph Pevney | Theodore Sturgeon | September 15, 1967 (1967-09-15) | 34 | 7.17 |
| 31 | 2 | "Who Mourns for Adonais?" | Marc Daniels | Gilbert Ralston | September 22, 1967 (1967-09-22) | 33 | 8.18 |
| 32 | 3 | "The Changeling" | Marc Daniels | John Meredyth Lucas | September 29, 1967 (1967-09-29) | 37 | 8.46 |
| 33 | 4 | "Mirror, Mirror" | Marc Daniels | Jerome Bixby | October 6, 1967 (1967-10-06) | 39 | 7.62 |
| 34 | 5 | "The Apple" | Joseph Pevney | Story by : Max Ehrlich Teleplay by : Max Ehrlich and Gene L. Coon | October 13, 1967 (1967-10-13) | 38 | 7.90 |
| 35 | 6 | "The Doomsday Machine" | Marc Daniels | Norman Spinrad | October 20, 1967 (1967-10-20) | 35 | 7.73 |
| 36 | 7 | "Catspaw" | Joseph Pevney | Robert Bloch | October 27, 1967 (1967-10-27) | 30 | 8.85 |
| 37 | 8 | "I, Mudd" | Marc Daniels | Stephen Kandel | November 3, 1967 (1967-11-03) | 41 | 8.23 |
| 38 | 9 | "Metamorphosis" | Ralph Senensky | Gene L. Coon | November 10, 1967 (1967-11-10) | 31 | 7.11 |
| 39 | 10 | "Journey to Babel" | Joseph Pevney | D. C. Fontana | November 17, 1967 (1967-11-17) | 44 | 7.28 |
| 40 | 11 | "Friday's Child" | Joseph Pevney | D. C. Fontana | December 1, 1967 (1967-12-01) | 32 | 8.74 |
| 41 | 12 | "The Deadly Years" | Joseph Pevney | David P. Harmon | December 8, 1967 (1967-12-08) | 40 | 9.91 |
| 42 | 13 | "Obsession" | Ralph Senensky | Art Wallace | December 15, 1967 (1967-12-15) | 47 | 9.18 |
| 43 | 14 | "Wolf in the Fold" | Joseph Pevney | Robert Bloch | December 22, 1967 (1967-12-22) | 36 | N/A |
| 44 | 15 | "The Trouble with Tribbles" | Joseph Pevney | David Gerrold | December 29, 1967 (1967-12-29) | 42 | 8.85 |
| 45 | 16 | "The Gamesters of Triskelion" | Gene Nelson | Margaret Armen | January 5, 1968 (1968-01-05) | 46 | 10.92 |
| 46 | 17 | "A Piece of the Action" | James Komack | Story by : David P. Harmon Teleplay by : David P. Harmon and Gene L. Coon | January 12, 1968 (1968-01-12) | 49 | 9.97 |
| 47 | 18 | "The Immunity Syndrome" | Joseph Pevney | Robert Sabaroff | January 19, 1968 (1968-01-19) | 48 | 9.46 |
| 48 | 19 | "A Private Little War" | Marc Daniels | Story by : Don Ingalls Teleplay by : Gene Roddenberry | February 2, 1968 (1968-02-02) | 45 | 9.52 |
| 49 | 20 | "Return to Tomorrow" | Ralph Senensky | John T. Dugan | February 9, 1968 (1968-02-09) | 51 | 10.14 |
| 50 | 21 | "Patterns of Force" | Vincent McEveety | John Meredyth Lucas | February 16, 1968 (1968-02-16) | 52 | 8.34 |
| 51 | 22 | "By Any Other Name" | Marc Daniels | Story by : Jerome Bixby Teleplay by : D. C. Fontana and Jerome Bixby | February 23, 1968 (1968-02-23) | 50 | 8.79 |
| 52 | 23 | "The Omega Glory" | Vincent McEveety | Gene Roddenberry | March 1, 1968 (1968-03-01) | 54 | 8.79 |
| 53 | 24 | "The Ultimate Computer" | John Meredyth Lucas | Story by : Laurence N. Wolfe Teleplay by : D. C. Fontana | March 8, 1968 (1968-03-08) | 53 | 8.74 |
| 54 | 25 | "Bread and Circuses" | Ralph Senensky | Gene Roddenberry and Gene L. Coon | March 15, 1968 (1968-03-15) | 43 | 12.10 |
| 55 | 26 | "Assignment: Earth" | Marc Daniels | Story by : Gene Roddenberry and Art Wallace Teleplay by : Art Wallace | March 29, 1968 (1968-03-29) | 55 | 8.79 |
* ↑ Credited as Jud Crucis
* ↑ Credited as John Kingsbridge

### Season 3 (1968–69)

After Star Trek's second season, word got around that NBC was prepared to cancel the show due to low ratings. Led by fans Bjo and John Trimble, Trek viewers inundated NBC with letters protesting the show's demise and pleading with the network to renew the series for another year. The president and vice-president of the television network, Don Durgin and Mort Werner, said in an interview that they received 115,000 letters, but that cancelling the show was "never our intention," and that it would be on the schedule in the favorable timeslot of Monday at 7:30p.m.
The network later changed the schedule so that Trek would air in the so-called "death slot"—Friday nights at 10:00 p.m. In addition to the "mismanaged" schedule, the show's budget was "seriously slashed" and Nichelle Nichols described the series' eventual cancellation as "a self-fulfilling prophecy".
Star Trek's final, 24-episode season began in September 1968 with "Spock's Brain". The third season also includes "The Tholian Web", where Kirk becomes trapped between universes; this episode would later be revisited by two 2005 episodes of the prequel series Star Trek: Enterprise. The last episode of the series, "Turnabout Intruder", aired on June 3, 1969, but Star Trek would eventually return to television in animated form when the animated Star Trek debuted in September 1973.
| No. overall | No. in season | Title | Directed by | Written by | Original release date | Prod. code | U.S. households (in millions) |
| 56 | 1 | "Spock's Brain" | Marc Daniels | Gene L. Coon | September 20, 1968 (1968-09-20) | 61 | 9.18 |
| 57 | 2 | "The Enterprise Incident" | John Meredyth Lucas | D. C. Fontana | September 27, 1968 (1968-09-27) | 59 | 6.67 |
| 58 | 3 | "The Paradise Syndrome" | Jud Taylor | Margaret Armen | October 4, 1968 (1968-10-04) | 58 | 7.58 |
| 59 | 4 | "And the Children Shall Lead" | Marvin Chomsky | Edward J. Lakso | October 11, 1968 (1968-10-11) | 60 | 7.98 |
| 60 | 5 | "Is There in Truth No Beauty?" | Ralph Senensky | Jean Lisette Aroeste | October 18, 1968 (1968-10-18) | 62 | 7.35 |
| 61 | 6 | "Spectre of the Gun" | Vincent McEveety | Gene L. Coon | October 25, 1968 (1968-10-25) | 56 | 7.70 |
| 62 | 7 | "Day of the Dove" | Marvin Chomsky | Jerome Bixby | November 1, 1968 (1968-11-01) | 66 | 7.98 |
| 63 | 8 | "For the World Is Hollow and I Have Touched the Sky" | Tony Leader | Hendrik Vollaerts | November 8, 1968 (1968-11-08) | 65 | 7.52 |
| 64 | 9 | "The Tholian Web" | Herb Wallerstein | Judy Burns and Chet Richards | November 15, 1968 (1968-11-15) | 64 | 7.64 |
| 65 | 10 | "Plato's Stepchildren" | David Alexander | Meyer Dolinsky | November 22, 1968 (1968-11-22) | 67 | 7.41 |
| 66 | 11 | "Wink of an Eye" | Jud Taylor | Story by : Gene L. Coon Teleplay by : Arthur Heinemann | November 29, 1968 (1968-11-29) | 68 | 8.72 |
| 67 | 12 | "The Empath" | John Erman | Joyce Muskat | December 6, 1968 (1968-12-06) | 63 | 9.86 |
| 68 | 13 | "Elaan of Troyius" | John Meredyth Lucas | John Meredyth Lucas | December 20, 1968 (1968-12-20) | 57 | 7.81 |
| 69 | 14 | "Whom Gods Destroy" | Herb Wallerstein | Story by : Lee Erwin and Jerry Sohl Teleplay by : Lee Erwin | January 3, 1969 (1969-01-03) | 71 | 6.84 |
| 70 | 15 | "Let That Be Your Last Battlefield" | Jud Taylor | Story by : Gene L. Coon Teleplay by : Oliver Crawford | January 10, 1969 (1969-01-10) | 70 | 7.92 |
| 71 | 16 | "The Mark of Gideon" | Jud Taylor | George F. Slavin and Stanley Adams | January 17, 1969 (1969-01-17) | 72 | 6.78 |
| 72 | 17 | "That Which Survives" | Herb Wallerstein | Story by : D. C. Fontana Teleplay by : John Meredyth Lucas | January 24, 1969 (1969-01-24) | 69 | 7.81 |
| 73 | 18 | "The Lights of Zetar" | Herb Kenwith | Jeremy Tarcher and Shari Lewis | January 31, 1969 (1969-01-31) | 73 | 8.09 |
| 74 | 19 | "Requiem for Methuselah" | Murray Golden | Jerome Bixby | February 14, 1969 (1969-02-14) | 76 | 6.95 |
| 75 | 20 | "The Way to Eden" | David Alexander | Story by : D. C. Fontana and Arthur Heinemann Teleplay by : Arthur Heinemann | February 21, 1969 (1969-02-21) | 75 | 7.07 |
| 76 | 21 | "The Cloud Minders" | Jud Taylor | Story by : David Gerrold and Oliver Crawford Teleplay by : Margaret Armen | February 28, 1969 (1969-02-28) | 74 | 7.58 |
| 77 | 22 | "The Savage Curtain" | Herschel Daugherty | Story by : Gene Roddenberry Teleplay by : Gene Roddenberry and Arthur Heinemann | March 7, 1969 (1969-03-07) | 77 | 6.73 |
| 78 | 23 | "All Our Yesterdays" | Marvin Chomsky | Jean Lisette Aroeste | March 14, 1969 (1969-03-14) | 78 | 7.41 |
| 79 | 24 | "Turnabout Intruder" | Herb Wallerstein | Story by : Gene Roddenberry Teleplay by : Arthur Singer | June 3, 1969 (1969-06-03) | 79 | 5.02 |
* 1 2 3 4 Credited as Lee Cronin
* 1 2 Credited as Michael Richards

## Production order

The list below details the series' episodes in production order, including the original series pilot, "The Cage". While the "complete season" DVD releases (listed above) follow the original broadcast order, the original episodic DVD releases are numbered by production order.
Pilots :
| 01 | "The Cage" |
| 02a | "Where No Man Has Gone Before" |
Season 1 :
| 02b | "Where No Man Has Gone Before" |
| 03 | "The Corbomite Maneuver" |
| 04 | "Mudd's Women" |
| 05 | "The Enemy Within" |
| 06 | "The Man Trap" |
| 07 | "The Naked Time" |
| 08 | "Charlie X" |
| 09 | "Balance of Terror" |
| 10 | "What Are Little Girls Made Of?" |
| 11 | "Dagger of the Mind" |
| 12 | "Miri" |
| 13 | "The Conscience of the King" |
| 14 | "The Galileo Seven" |
| 15 | "Court Martial" |
| 16 | "The Menagerie, Parts I and II" |
| 17 | "Shore Leave" |
| 18 | "The Squire of Gothos" |
| 19 | "Arena" |
| 20 | "The Alternative Factor" |
| 21 | "Tomorrow Is Yesterday" |
| 22 | "The Return of the Archons" |
| 23 | "A Taste of Armageddon" |
| 24 | "Space Seed" |
| 25 | "This Side of Paradise" |
| 26 | "The Devil in the Dark" |
| 27 | "Errand of Mercy" |
| 28 | "The City on the Edge of Forever" |
| 29 | "Operation -- Annihilate!" |
Season 2 :
| 30 | "Catspaw" |
| 31 | "Metamorphosis" |
| 32 | "Friday's Child" |
| 33 | "Who Mourns for Adonais?" |
| 34 | "Amok Time" |
| 35 | "The Doomsday Machine" |
| 36 | "Wolf in the Fold" |
| 37 | "The Changeling" |
| 38 | "The Apple" |
| 39 | "Mirror, Mirror" |
| 40 | "The Deadly Years" |
| 41 | "I, Mudd" |
| 42 | "The Trouble with Tribbles" |
| 43 | "Bread and Circuses" |
| 44 | "Journey to Babel" |
| 45 | "A Private Little War" |
| 46 | "The Gamesters of Triskelion" |
| 47 | "Obsession" |
| 48 | "The Immunity Syndrome" |
| 49 | "A Piece of the Action" |
| 50 | "By Any Other Name" |
| 51 | "Return to Tomorrow" |
| 52 | "Patterns of Force" |
| 53 | "The Ultimate Computer" |
| 54 | "The Omega Glory" |
| 55 | "Assignment: Earth" |
Season 3 :
| 56 | "Spectre of the Gun" |
| 57 | "Elaan of Troyius" |
| 58 | "The Paradise Syndrome" |
| 59 | "The Enterprise Incident" |
| 60 | "And the Children Shall Lead" |
| 61 | "Spock's Brain" |
| 62 | "Is There in Truth No Beauty?" |
| 63 | "The Empath" |
| 64 | "The Tholian Web" |
| 65 | "For the World Is Hollow and I Have Touched the Sky" |
| 66 | "Day of the Dove" |
| 67 | "Plato's Stepchildren" |
| 68 | "Wink of an Eye" |
| 69 | "That Which Survives" |
| 70 | "Let That Be Your Last Battlefield" |
| 71 | "Whom Gods Destroy" |
| 72 | "The Mark of Gideon" |
| 73 | "The Lights of Zetar" |
| 74 | "The Cloud Minders" |
| 75 | "The Way to Eden" |
| 76 | "Requiem for Methuselah" |
| 77 | "The Savage Curtain" |
| 78 | "All Our Yesterdays" |
| 79 | "Turnabout Intruder" |

## British transmission

Star Trek was first broadcast in the United Kingdom on BBC One starting on July 12, 1969, with the episode "Where No Man Has Gone Before". The first episode broadcast in color was "Arena" on November 15, 1969. The episodes were broadcast in a different order than in the United States and were originally aired in four seasons between 1969 and 1971. The BBC edited the episodes for broadcast by showing the title sequence first, then the teaser segment that aired before the titles in the United States, then the rest of the episode. These edited episodes aired until the 1990s, after which the BBC was supplied with NTSC videotape transfers of the first season instead of new film prints, resulting in a substandard picture, and with edits originally made for syndication in the United States. Viewer complaints led to the BBC obtaining film prints for the subsequent two seasons.
"The Cage" was first broadcast on Sky One in July 1990. Three episodes, "Plato's Stepchildren", "The Empath", and "Whom Gods Destroy", were not broadcast on the BBC until 1994, although "The Empath" was listed in the Radio Times as scheduled to broadcast on December 16, 1970, at 7:20 pm. Sky One was the first network to air these three episodes in the UK in 1990, although with the title sequence and teaser shown in the order as they were aired in the United States, whereas the rest of the episodes were broadcast as edited by the BBC.