Star Trek III: The Search for Spock is, as its title suggests, the third feature-length Star Trek film. It was directed by Leonard Nimoy and stars the cast of the original series. It also stars Christopher Lloyd as the Klingon antagonist, Merritt Buttrick as David Marcus (Kirk's son) and Robin Curtis as the Vulcan Saavik (Kirstie Alley, who played Saavik in Star Trek II, wanted more money than the producers were prepared to spend).
Summary (without spoilers)
The USS Enterprise is scheduled for decommissioning after the events of Star Trek II. Dr. McCoy is acting strangely, and a conversation with Spock's father leads Kirk to want to return to the Genesis planet. Meanwhile, a nefarious band of Klingons are after the secrets of the Genesis torpedo.
Summary (with spoilers)
Spock (believing that the needs of the many outweigh the needs of the few or the one) nobly put himself at risk in order to repair the USS Enterprise's warp drive at the end of Star Trek II. He succumbed to the radiation poisoning shortly thereafter. He was given a space burial and the torpedo casing containing his remains landed on the newly created Genesis planet.
Before attempting to fix the warp drive, Spock transferred his katra, or living spirit, to Dr. McCoy, through a mind meld.
Once the Enterprise crew returns to Earth, McCoy begins to act strangely and receives treatment. The crew is informed that the Enterprise is not going to be repaired due to its age and the extensive damage it sustained in the battles depicted in Star Trek II. Kirk receives a visit from Ambassador Sarek, who's a bit miffed about the fact that his son's remains weren't returned to Vulcan as well as about Kirk not doing anything with his katra. Kirk is confused at first, since he's never heard of a katra, but the two eventually figure out that it was transferred to McCoy.
Sarek explains that both Spock and McCoy are in pain and will remain in pain until they are brought to Vulcan. Kirk vows to make it happen, though Starfleet command forbids it. Genesis has, apparently, become something of a controversy. Meanwhile, McCoy tries to hire a ride to the planet and ends up arrested by security guards.
Of course, Kirk has decided to go to Genesis anyway. The crew springs McCoy and brings him to a teleportation room staffed by Uhura, who promises to meet up with them later and beams them aboard the Enterprise. Scotty has been making the repairs himself and, when the new USS Excelsior is ordered to pursue, its warp drive fails because Scotty sabotaged it.
In the meantime, Kirk's son, David, and Lieutenant Saavik are part of the Starfleet-approved scientific expedition to the Genesis planet on board the USS Grissom. They beam down to the planet after the ship's equipment detects life forms on its surface. It turns out to have been rapidly evolving organisms, but they also find that the torpedo casing that held Spock's remains is empty. They also find a Vulcan boy on the planet; he can't speak, but they surmise that the Genesis effect could have regenerated Spock's cells.
David and Saavik want to bring the boy back up to the ship, which destroyed by Klingons in pursuit of the Genesis information. The Klingon leader, Kruge, wanted to disable the ship so as to be able to take prisoners and retrieve all possible information about the Gensis planet, but a "lucky shot" blew the whole thing up. Kruge is kind of ruthless and he vaporizes the crewmember who accidentally destroyed the Grissom. But all is not lost for the Klingons as they realize there are people on the planet. They plan to beam down and take them hostage.
The planet is acting strangely, moving through the seasons at an irregular pace. Further to that, the "mysterious Vulcan boy" is aging at an accelerated rate. David admits he used protomatter, which is highly unstable and has been condemned by most scientists. The boy, now roughly a teenager in terms of biological development, begins to go through pon farr and Saavik helps to ease the situation by mating with him.
The Enterprise's crew hears Starfleet send the Grissom a warning about them, since they've kind of stolen a starship, and Kirk decides to try to mitigate possible damage by contacting the Grissom directly. Of course, there's no answer. The Klingons beam down to the planet and take David, Saavik and the mysterious Vulcan boy hostage.
The Enterprise spots the Klingon bird-of-prey and a battle ensues, with both ships doing the other serious damage. The Enterprise has sustained the worst damage, however, though Kirk attempts to bluff the Klingons into surrendering. He's permitted to speak to the hostages, David admits again that the Genesis experiment failed, and Kruge decides to order his men to kill somebody. He doesn't care who.
The Klingons on the planet choose Saavik, but David moves in to save her in time and is killed in the process.
Kirk is able to put his grief aside long enough to come up with a cunning plan. He tells Kruge he surrenders and that his crew should prepare to board the Enterprise. He sends McCoy and Sulu to the transporter room and then he, Scotty and Chekov activate the Enterprise's self-destruct sequence. They then beam off the ship onto the planet. The Klingons beam onto the ship, which promptly explodes.
The mysterious Vulcan really is Spock, having aged to the precise age Spock was when he died. McCoy confirms that he's physically healthy but that there's a void where his mind should be ("... I've got all his marbles.")
Kruge beams down to the planet to find the crew, Saavik, Spock and the surviving members of his posse (who were on the planet when the Enterprise exploded). Everyone but Kruge, Kirk and Spock is beamed aboard the bird-of-prey and a battle ensues.
Kirk eventually disposes of Kruge and uses his limited Klingon skills to get himself and Spock beamed aboard the ship.
The crew flies to Vulcan, where Sarek and Uhura are waiting. Sarek requests a refusion of Spock's body and katra, even though such a procedure has never been attempted outside of legend. McCoy agrees to the risks involved, and the Vulcan high priestess T'Lar manages to pull it off successfully.
I happen to find Star Trek III to be underrated. It may be true that the odd-numbered films aren't as good as their even-numbered counterparts, but I'd argue that III is easily the best of the odd-numbered offerings featuring the original crew. Of course, it doesn't take much to be better than Star Trek: The Motion Picture and especially Star Trek V: The Final Frontier, but this is different. I don't merely tolerate Star Trek III, I enjoy it. Maybe not as much as I enjoy Star Trek II or Star Trek VI, but I enjoy it all the same.
Star Trek II left us with Spock dead, a new planet and Kirk finally getting over his mid-life crisis. III picks up exactly where II left off and then proceeds to erase almost everything that's happened by the conclusion of II (short of the resurrection of Khan). Spock comes back, David goes away and the planet self-destructs. And yet even though it's a two-hour exercise in erasing several of the events of a previous movie, it's entertaining. Sure, it has its share of cheese (the sets! Certain dialogue! That scene in the bar!), but it makes me smile anyway.
Of course, the danger in all this is that I saw it and then thought "That wasn't that bad! I guess people just mean that the odd-numbered ones aren't as good as the even-numbered ones" and then proceeded to rent Star Trek V. I regret the error.
As for my favourite part, I admit it to being a giant sap. Between Kirk defeating Kruge and the crew arriving on Vulcan, we shift to a brief scene between Spock and McCoy on the bird-of-prey. Spock remains unconscious but McCoy attempts to get him to wake up so he can tell him what to do with "this thing in my head." Then his demeanor softens and he says that he never thought he'd say it, but he missed the Vulcan and doesn't know whether he "could stand to lose (him) again."
Aww. Who saw that coming (other than people like me who long suspected that the two were secretly best friends the whole time)? If you're like me, and you saw the films before you saw much of the original series, the scene may have affected your perception of their relationship. Sure, they were always bickering and McCoy was forever going out of his way to tell Spock he didn't like him, but he'd miss him once he was gone.
And besides, as one of my Star Trek-loving coworkers once said, "No one speaks Klingon better than Christopher Lloyd." Can you really argue with that?
also has a small part as an officer on the USS Grissom, and Grace Lee Whitney
makes a cameo as Janice Rand.