Star Trek (1966–1969)
21 user 6 critic

All Our Yesterdays 

When Kirk, Spock and McCoy investigate the disappearance of a doomed planet's population, they find themselves trapped in different periods of that world's past.


(as Marvin Chomsky)


(created by),

Watch Now

With Prime Video


Comic-Con 2017: All Aboard the IMDboat


July 20 to 23, 2017

Get entertainment news, trailer drops, and photos with IMDb's coverage of 2017 San Diego Comic-Con featuring host and IMDboat captain Kevin Smith. Watch our exclusive celebrity interviews, and tune in to our LIVE show from 3:30 to 5 p.m. PDT on Saturday, July 22.

Browse Our Guide to Comic-Con



Episode complete credited cast:
Kermit Murdock ...
Ed Bakey ...
The First Fop
Scott (voice)
Anna Karen ...
Sarpeidon Mort
Albert Cavens ...
Second Fop (as Al Cavens)
Stan Barrett ...
The Constable


When the planet Sarpeidon is about to be destroyed by its star Beta Niobe becoming a supernova, Kirk, Spock and McCoy beam down and find it evacuated except for its librarian, Mr. Atoz, tending with his replicas a collection of unusual discs, which play the planet's history and (to their surprise) allow their users to travel into the past trough the atavachron, a time machine, into the periods each was studying on disc, but they travel unprepared. McCoy and Spock find themselves locked in a frozen ice age 5,000 years ago, where Spock reverts to the barbaric age of the Vulcans, hence touchy and intensely attracted to the political prisoner Zarabeth, who enjoys getting company but tells them return is impossible. Kirk arrives in a Cromwellian period, where he's arrested and suspected of witchcraft, but realizes the magistrate must be a time traveler like him, and learns not being prepared at molecular level he can return through the time portal, and in fact must do so and contact Spock ... Written by KGF Vissers

Plot Summary | Add Synopsis


See all certifications »


Official Sites:



Release Date:

14 March 1969 (USA)  »

Company Credits

Show detailed on  »

Technical Specs


Sound Mix:


Aspect Ratio:

1.33 : 1
See  »

Did You Know?


Scotty's voice is heard over a communicator, but he is never seen in this episode. See more »


When Spock and Zarabeth are talking, Spock turns to see McCoy standing at the cave entrance and McCoy says, "You've been dishonest with me, Spock," but his lips don't move. See more »


Zarabeth: What are you called?
Mr. Spock: I'm called Spock.
Zarabeth: [smiles] Even your name is strange.
See more »

Frequently Asked Questions

This FAQ is empty. Add the first question.

User Reviews

The wonders of the Atavacron
6 September 2014 | by (Buffalo, New York) – See all my reviews

Watching this particular Star Trek episode I find it hard to believe that a humanoid civilization that was able to master time travel as well as it did could not master space travel at all. Then again had they done so we would not have this episode at all.

Kirk, Spock, and McCoy are an away team which beams down to a planet which has a humanoid civilization and orbits a sun about to go supernova in a matter of hours. All they find a library with a Gazillion discs showing the planet's history. The librarian Ian Wolfe and his duplicates are all that is left.

William Shatner goes through the portal called the Atavacron after he hears a scream coming from the other side. He finds himself in a world that resembles Restoration England with people costumed that way. When Leonard Nimoy and DeForest Kelley follow Shatner through they are in a prehistoric Ice Age and they are given shelter by Mariette Hartley who is an exile of sorts and understandably lonely for some company.

I won't go into how the three got out of their predicament, but going back through time won't solve the planet's problem with the supernova when it does come. Unless those that go back change history so that research into space travel is done. I would have exacted that pledge from those going through the Atavacron.

Interesting story, but the series has done better.

3 of 9 people found this review helpful.  Was this review helpful to you?

Contribute to This Page

Create a character page for: