For those of you who don't know, the plot follows the exploits of the crew of the Starship Enterprise in the 23rd century as they exploe the universe.
Lets start with the negatives; the special effects are dated and the plotlines are more than a little bit weak. Having said that the acting is surprisingly good and despite the dodgy dialoguereally easy to watch.
The real thing to remember though is that this was the birth of sci-fi as we know it and in many respects the marker by which all other sci-fi is measured. If you like sci-fi you will love this - particularly if you like old sci-fi.