To Boldly Go, Part I

With the five-year mission almost over and the Enterprise due home for a refit, Kirk is still troubled by the loss of several sister ships. A distress call diverts him to Aldebaran III, where a colony has fallen silent and Starfleet has been running a secret laboratory. Past the outpost's automated defences, the landing party finds Lana, a survivor with powers like those Gary Mitchell gained at the galactic barrier, who reveals that Starfleet has been trying to create and weaponise Espers. An apparent Romulan intruder is overpowered, and with the other test subjects seemingly carried off by Romulans, the Enterprise gives chase. A warbird under the Romulan Commander whom Spock once deceived intercepts them, and the old adversaries agree to cooperate. The hunt proves to be a ruse: there was no Romulan raider. The captured intruder is Sentek, an Aldebaran Vulcan, an Esper and Lana's husband, while the remaining Espers fled aboard the Halifax towards the barrier. Joining their engines, the Enterprise and the warbird race to the galaxy's edge, only to see the USS Kongo emerge from the barrier with its crew dead and the Espers in command. Aboard the Enterprise, Lana breaks out of the brig, using her mind to make Lieutenant Drake and another guard kill themselves, and she and Sentek head for the bridge.