Memory Beta, non-canon Star Trek Wiki
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[]

  • This character could be either Clifford Brent or Vinci, as they were played by the same actor and the character wasn't named in this episode. He is assumed to be Brent based on his blue or yellow uniform.
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