Windows on a Lost World (Star Trek: The Original Series #65) by V.E. Mitchell….
While Kirk, Spock, Chekov and an archaeological team are exploring the ruins of an ancient civilization on the uninhabited planet Careta IV, they discover strange devices that appear to be simple windows. But the windows prove dangerous when Kirk and Chekov enter them, and disappear. Now, while the two struggle to survive, Spock struggles to unravel the mystery while fighting off aliens.
It’s Trek books like this make it hard to finish this challenge.. I me wow… Normally they are fun to read and you go into them not really looking for high literary quality. But this was like pulling teeth just to get through. A lot of the characters do not act like they should. Completely out of character, specially Bones and Chekov. It seems the author had no knowledge of the history of the show and/or just didn’t care. That’s how it comes off in this whole novel. The plot drags on and on and quickly goes nowhere.. I think this is the first time the Original Series novels were this bad.. I might be wrong, I’ll have to go back and look. But wow, this one is the worst so far. 
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