There is no need for me to recount the moments or plotting of the show since that is readily available to the reader by using a few clicks of the mouse, and a little keyboard action. (I did some work for the reader: energize.) This posting is more about my impressions on the episode after seeing almost nothing of the program in years. (It's like having been in a Slaver Stasis Box... maybe.)
Although, needless to say, the animation by Filmation is very limited the series' ideas still come through, and do so with some style. The original actors do the voices for the beloved characters, which helps the rather static and inanimate faces get the points across without the viewer having to do too much "in-betweening". The backgrounds are at times rich and lovely, a benefit of being able to illustrate anything you want in the inexpensive medium of paint-on-acetate. Due to the very limited budget of a Saturday Morning Cartoon, tricks are used to save on expensive man-hours: in order to conserve on actual animation the producers could let a character's voice-over run the show as the camera slowly panned on a background; and the characters remained still as they talk away.
One thing that struck me now that I'm a more-or-less fully-functioning adult person is how adult this episode is in its ideas and richness of story-detail (certainly for a 25 minute episode). The interplay between the arrested starship crew and the renegade Kzinti contains the expected battle-of-wits, and although trapped by the limiting formats of episode length and basic animation, the scenes have some snap. Mr. Spock, Sulu, and Uhura swap technical info and barbs amongst one another, sans subtle facial reactions, but somehow it all works. There is an inherent dryness brought on by the need to tell a fair bit of story in a short time frame, but things move at a clip -- this may be one of the more kiddie-friendly aspects of the animated Star Trek.
Now that I've had my special little screening, I want to see more of the animated Star Trek series.