Synopsis for
Star Trek: The Wrath of Khan (1982) More at IMDbPro »

The crew of the USS Defiant visit planet Ceti Alpha V, much to their regret. Forgotten by the Federation, this was the planet Khan Noonien Singh (Ricardo Montalban) and his band of genetically-engineered supermen were dumped by Admiral James T. Kirk (William Shatner) decades earlier. Pavel Checkov (Walter Koenig) and his Captain (Paul Winfield) are taken prisoner, and have an unpleasant-looking mind control worm placed in their heads. This allows Khan and his henchmen to seize the Defiant .

Grilling the captain of the Defiant, Captain Terrell, and Chekov (Walter Koenig) Khan learns that a super-secret new tool, the Genesis Device, is being readied for testing not far away. He goes to the base, kills virtually everyone, but does not obtain the device.

Meanwhile, Admiral Kirk is inspecting the trainee crew, learning the ropes on Enterprise. He receives a distress call from the Genesis base, and heads there. Encountering the Defiant, he is unconcerned until the other ship powers up weapons and attacks. The Enterprise is caught off-guard and is badly damaged.

Kirk goes to the base, finding the scientists murdered and the apparently abandoned Terrell and Chekov. Using the transporter, they beam down to the planet the spacestation orbits and find his former lover Dr. Carol Marcus (Bibi Besch) and his Son David (Merritt Buttrick). They explain that the Genesis Device is hidden in a deep cavern, and show it to Kirk. Meanwhile, Terrell and Chekov reveal they are still under Khan's control. Once they have located Genesis for him, he beams it onto his ship.

The Genesis Device has the ability to re-encode the molecules of a planet, creating life where there was none before. Khan sees it as a useful tool for setting up a base somewhere, and makes off with it. He thinks that Kirk is trapped in the underground cavern, but the Enterprise has been largely repaired and saves Kirk.

The Enterprise lures Reliant into a gaseous nebula, baiting Khan and causing him to act irrationally. Kirk eventually ambushes Reliant, wrecking the smaller vessel. Khan activates the Genesis Device, knowing that the blast wave from it will re-organize the molecules of Enterprise and its crew, killing them. The Enterprise's warp drive is off-line from the earlier battle, and she cannot escape in time... unless... At the last minute, Spock decides to sacrifice his life by entering the radiation-filled engine room and fixing the broken warp drive. The plan works, but the cost is high. Khan's ship explodes as Kirk's rockets away.

The Genesis Device rejuvenates the nebula into a star and the liveless world the spacestation orbitted, into a life-filled planet. The Enterprise crew fires Spock's radiation-ravaged corpse onto the surface as Scotty (James Doohan) plays "Amazing Grace" on his bagpipes.