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Memory Beta, non-canon Star Trek Wiki

"Tomorrow is Yesterday" was the 21st episode of Star Trek: The Original Series produced in the show's first broadcast season, first aired on 26 January 1967. The episode was written by D.C. Fontana, directed by Michael O' Herlihy and novelized in Star Trek 2 by James Blish.



Episode characters

Robert AbramsClifford Brent[1]John ChristopherLucas FelliniBill HadleyJames T. KirkJohn KyleRyan LeslieLeonard McCoyMontgomery ScottSpockHikaru SuluNyota UhuraWebbUSS Enterprise computerunnamed US military personnel (Air Police staff sergeant)
Referenced only
Shaun Geoffrey Christopher

Novelization characters

AmesJohn ChristopherJames T. KirkLeonard McCoyMontgomery ScottSpockHikaru SuluNyota Uhura
Referenced only
Shaun Geoffrey Christopher


EarthOmaha, Nebraska

Starships and vehicles

Bluejay 4 (F-104 Starfighter) • USS Enterprise (Constitution-class heavy cruiser)

Races and cultures


Technology and weapons


Materials and substances


States and organizations

FederationStarfleetUnited States Air ForceVegan Tyranny

Ranks and titles

captaincommandercommanding officercommunications officerFederation Starfleet ranksFederation Starfleet ranks (2260s)first officerlieutenant commanderofficerscientistscience officer

Other references

anatomyarmbootclothingFederation membersfingerfive-year missiongovernmenthumanoidlanguagelifeformlogicmattermemorynation-stateorbitpantsquadrantraces and culturesrankspacestarstardateStarfleet uniformStarfleet uniform (2260s)technologytitletunicuniformuniverseweaponSlingshot effectchicken soup


Related media

Novel adaptations

Video releases


Episode images

Adaptation images



published order
Previous episode:
The Alternative Factor
TOS episode produced Next episode:
The Return of the Archons
Previous episode:
TOS episode aired Next episode:
Court Martial
Previous story:
A Taste of Armageddon
Star Trek 2
Next story:
Errand of Mercy
chronological order
Previous Adventure:
The Alternative Factor
Pocket Next Adventure:
Web of the Romulans
Previous Adventure:
The Alternative Factor
Voyages of the
USS Enterprise (NCC-1701)
(2264 to 2270)
Next Adventure:
Vicious Circle!

External links

  1. This character was not named in the episode but the same actor, wearing an officer's Starfleet uniform, was addressed as Brent in TOS episode: "The Naked Time". The same actor also played the character of Vinci.