Upon his return from a journey through the Guardian of Forever Kirk realizes that history has been altered and no one remembers Spock. An Andorian is now his First Officer and it appears that Spock met an untimely death during a childhood ritual on Vulcan. Spock must use the Guardian again and return to the Vulcan of his youth and restore his time line.
Did You Know?
There are a number of mistakes concerning the Guardian Of Forever. In Star Trek: The Original Series: The City on the Edge of Forever
it was surrounded closely by ruins. In this cartoon it is shown in a clearing with only remnants of them. The voice was originally quite deep, and slightly enhanced electronically. The entire "ring" flashed in synchronization with its speech. Here the voice is much higher pitched; sounding old and weak. There is no flashing during its dialogue. Additionally, it now has the ability to "prepare" a time and place to receive the time traveler where as it originally could only show the past like an extremely sped up film. Reaching the exact time and place desired required careful calculations with no guarantee of complete success. See more
A Vulcan would face such a loss without tears.
By understanding every life comes to an end when time demands it. Loss of life is to be mourned, but only if the life was wasted.
Referenced in Star Trek