Season Three starts off with a strange being showing up on the Enterprise and removing Spock's (Leonard Nimoy) brain from his body. When they find the planet where the strange woman came from, they find a civilization where cavemen live on top and an advanced society lives underground, though no one from the underground knows how anything works and they behave like children. They soon find out that Spock's brain is being used as a computer for the whole planet.
Another good episode is "The Enterprise Incident" where Kirk (William Shatner) apparently goes rogue and has the Enterprise move into the Romulan Neutral Zone and then into Romulan space. Here, they are immediately confronted by three Romulan ships (as expected) and a series of events happen that make it appear as if Spock is planning to defect to the Romulans and hand over the Enterprise itself.
In "Spectre of the Gun," the crew is transported into a strange world the represents the Old West. Kirk, Spock, Scotty (James Doohan), McCoy (DeForest Kelley), and Chekov (Walter Koenig) are put in the place of the Clantons. Kirk realizes that they are in a strange form of Tombstone and apparently destined to go through the events of the O.K. Corral - where the Clantons lost their lives. Obviously, the crew has to find a way to keep the same thing from happening to them.
Other great episodes include "Wink of an Eye" where Kirk is sped up so fast that the rest of his crew appears to be standing still and "Let That Be Your Last Battlefield" where two people from a strange race show up who have faces that are half black and half white. This particular episode focuses a lot on racism, since the society is very different for those who have black on the right side instead of white.
Another odd, but classic episode is "The Savage Curtain" where Kirk and Spock go down to a planet that has both Abraham Lincoln and a Vulcan figure named Surak. The four must face off against some of the greatest foes in history including Genghis Khan, Colonel Green, Zora, and the Klingon Kahless the Unforgettable.
The season and series ends with an episode where one of Kirk's former lovers takes over Kirk's body. What exactly is this woman's plan, only she knows, but it will lead to the possible court marshaling of Spock.
What I enjoyed was the inclusion of the original pilot "The Cage" featuring Captain Pike. In the non-remastered DVD release, this was included in Season One. Instead they put it here (which I guess makes sense since it was aired many years after the series ended). This boxed set contains both the original and remastered versions, so you can view it either way.
Like the past two Remastered sets, not only are there a lot of touched up visuals (though there is a good bit of debate over whether those classic, cheesy effects should be altered), but a whole slew of extras about this particular season and Star Trek in general. Trekkers that don't mind the film being cleaned up and the special effects being modernized will probably really enjoy this boxed set. I know I did. Though, if you already picked up the fairly recent, non-remastered DVD set, then this probably isn't a good purchase. But those who haven't picked up The Original Series yet should look into this set.