When the planet Sarpeidon is about to be destroyed, by its star Beta Niobe becoming a supernova, Kirk (William Shatner), Spock (Leonard Nimoy) and McCoy (DeForest Kelley) beam down and find it evacuated except for its librarian, Mr. Atoz (Ian Wolfe), tending to his replicas. They are a collection of unusual discs, which play the planet's history and (to their surprise) allow their users to travel into the past through the atavachron, a time machine, into the periods each was studying on disc. The crew travels 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. He becomes very easily agitated, and is intensely attracted to the political prisoner Zarabeth (Mariette Hartley), who enjoys getting company but tells them return is impossible. Kirk arrives in a Cromwellian period, where he's arrested and suspected of witchcraft. He soon realizes the magistrate must be a time traveler like him, and ...
Did You Know?
This is the penultimate episode of the original Star Trek series. See more
When Bones and Spock return through the portal, they leave the past wearing fur coats - they arrive in The Library without the coats. The coats are from the ice age, and like a person who had been "prepared" by the atavachron (the time portal machine), they cannot survive traveling forward in time. See more
There's no further need to observe me, Doctor. As you can see, I've returned to the present in every sense.
But it did happen, Spock.
Yes, it happened. But that was five thousand years ago. And she is dead now. Dead and buried. Long ago.
Special Enhanced version Digitally Remastered with new exterior shots and remade opening theme song See more
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