It's been a long time since I have watched this episode but as I remember it it was fairly good. The show always had a way of taking you "out there". I thought the acting wasn't the best with this episode but the basic jist of what was going on was pretty incredible. I think that the librarians purpose in this one to make sure that everyone on the planet was sent somewhere do to some catastrophic event about to occur ( I think a nova/super nova or something). Kirk, Spock and Bones beam down to the distressed planet only to learn that they must go somewhere thru the dimensional doorway "for their own good" by the psycho librarian. I believe that they discover that the librarian has already dispatched all the other citizens of the planet. Obviously, the crew doesn't want the do this but the librarian forces them thru the doorway anyway. Kirk is sent to a place that looks like Salem (during the period of the witchhunts) or something and is suspected of being a witch (I guess because he was talking to a brick wall, looking for the doorway he come thru and was wearing funny clothes). He gets the prosecutor to let him out of the jail cell and of course finds his way back thru the doorway to the library. During Kirk's ordeal, Bones and Spock are sent to a glacial age where they meet an attractive girl?? Bones and Spock vi for her love. Spock someone begins turning savage however and obviously Bones is no match for his super human strength. Of course they also go back thru the doorway to the library eventually. However, both long for the company of the woman they left.
The crew confronts the librarian (which I believe has clones of himself to help dispence of troublemakers)and the librarian eventually flees thru the doorway (I guess saying the "heck" with the crew..I'm saving myself). The crew makes it back to the ship and apparently sail off into oblivon being this is the last episode. Not to bad of way to go out I guess....Any comments?