the next to last episode air of the original star trek series be an interesting and sometimes melancholy installment that prove the show be still explore it character even at this point in the third season while though flawed and all our yesterday have it moment and overall a moody and compel feel to it . kirk and spock and and mccoy beam down to a planet and assume they be arrive in the nick of time to save or at least give some warning to whatever populace be there and since the planet sun be due to explode within hour . but a it turn out and the people there be all too aware of the planet fate and and use a kind of time travel device and have escape into the past . each person have be able to choose the time and place in the past where he or she would like to live at a library and run by an elderly man name mr. atoz . atoz assume the three men be look for a past to live in as well and and show them various period from which they can choose on viewer . there be some rather force confusion at the start of the episode and with line like representmccoy where do they go . atoz wherever they want to . the misunderstanding could be clear up rather easily and but for plot purpose and it isn not and and soon kirk find himself transport back to a period resemble 18th century england and while spock and mccoy be send to an ice age and 5000 year in the planet past . from here and the main focus be on spock and his relationship with a woman exile to this time by a tyrant a punishment . spock begin act increasingly emotional and show anger toward mccoy and deep affection for zarabeth and the woman . he eventually realize that he be revert back to the primitive emotional state of his ancestor on vulcan and 5000 year ago . kirk make his way back to the library first and and finally convinces mr. atoz they do not belong in his planet history . spock and mccoy return just before it too late and leave zarabeth behind while the enterprise beam the three up and speed away a the sun explodes and destroy the planet . the interaction between spock and zarabeth provide this episode most memorable moment and though kirk adventure into the english past be amuse . all in all and a very decent latter day star trek outing .