"Tomorrow Is Yesterday"
Series Star Trek
Season 1, Episode 19
TOS 1x19 006
Air date January 26th, 1967
Writers D.C. Fontana
Director Michael O'Herlihy
Producers Gene L. Coon; Gene Roddenberry; Robert H. Justman
Starring William Shatner; Leonard Nimoy
Episode guide
"Court Martial"

"Tomorrow Is Yesterday" is the eighteenth episode of season one of the original science fiction/adventure series Star Trek, and is the twenty-first episode produced in the series overall. It was directed by Michael O'Herlihy with a script written by D.C. Fontana. It first aired on NBC on January 26th, 1967. In addition to the regular cast and recurring stars, this episode features guest appearances by actors Roger Perry as Captain John Christopher, Hal Lynch as an Air Police sergeant, Richard Merrifield as Technician Webb and Ed Peck as Colonel Fellini.

Synopsis Edit

Cast Edit

Principal Cast Edit

Actor Role
William Shatner Captain James T. Kirk
Leonard Nimoy Mr. Spock

Also starring Edit

Actor Role
Roger Perry Major Christopher

Featuring Edit

Actor Role
DeForest Kelley Dr. McCoy
Hal Lynch Air Police sergeant
Richard Merrifield Technician
John Winston Transporter chief
Ed Peck Colonel Fellini

With Edit

Actor Role
James Doohan Scott
George Takei Sulu
Nichelle Nichols Uhura
Mark Dempsey Air Force Captain
Jim Spencer Air policeman
Sherri Townsend Crew woman

Uncredited cast Edit

Note: The following is taken from the full credits list for this entry on IMDB. As it is a website with user-submitted information, some of the data listed here, including character names may be inaccurate.

Actor Role
Majel Barrett Enterprise computer
Bill Blackburn Engineer
Frank da Vinci Lieutenant Clifford Brent
Eddie Paskey Lieutenant Ed Leslie

Notes Edit

Background information Edit

  • Actor Leonard Nimoy is credited with an "Also starring" prefix in the opening title credits, as well as his character's name, Mr. Spock.
  • Music for this episode was composed and conducted by Alexander Courage.
  • There are total of seventeen on-screen characters in this episode. There are 15 male characters and 2 female characters. 12 of the characters are given proper names either in this episode, or in some other external source.
  • Mister Spock is the only non-human character featured in this episode.

Redirects Edit

The following links redirect to this page. Some of the links may also be used as shortcuts for quick reference to this page.

Setting Edit

  • The setting for the main timeline is the 23rd century in the year 2267; Stardate: 3113.2.

Character names Edit

  • James Doohan's character is identified only as Scott in this episode. The character's full name and rank is Chief Engineer Montgomery Scott.
  • Ed Peck's character's name is spelled with the shortened Col. Fellini, as opposed to Colonel Fellini.

Trivia Edit

  • Technician Webb is the first character seen in this episode. He is also the first character with speaking lines.
  • John Christopher's military service number is 4857932.

What else have they done? Edit

  • This is Mark Dempsey's only work in the science fiction genre. He is also known for playing several characters on episodes of 77 Sunset Strip. He has also appeared in episodes of Hawaiian Eye and Perry Mason.
  • This is the first, and to date, only known acting work for Sherri Townsend, who plays a crew woman in this episode.

Allusions Edit

  • Captain Christopher tells Mister Spock that he doesn't believe in little green men. "Little Green Men" is a generic term used by people of Earth to describe beings from another planet; usually in a glib manner. This stems from an erroneous stereotype that all aliens have green skin and are short in stature. "Little Green Men" is also the title to episode 4x07 of Star Trek: Deep Space Nine.

Bloopers Edit

  • Mister Spock's ears look noticeably fake in the opening scene from this episode.
  • The character of John Christopher is identified as a Major in this episode, when he is in fact a Captain.

Quotes Edit


  • Spock: I made an error in my computations.
  • Leonard McCoy: Oh? This could be an historic occasion.


  • Leonard McCoy: Blast your theories and observations, Mr. Spock! What about Jim? He's down there alone, probably under arrest! He doesn't have a communicator and we can't locate him or beam him back aboard without one!
  • Spock: I am aware of that, Doctor.

Appearances Edit

See also Edit


The World of Star Trek

Star Trek miscellaneous

External Links Edit

Series links

Episode links