James Tiberius Kirk is the legendary captain of the Starship Enterprise in the original Star Trek TV series. Kirk's adventures saw him brave many terrible dangers, make countless astronomical discoveries, and of course, court several alien women. He was portrayed by William Shatner throughout the original series and the first seven Star Trek films.
Captain Kirk dies in Star Trek: Generations, the seventh film in the Star Trek franchise. His death, unfortunately, seems to lack much of the glamour and flair that Starfleet's finest captain was famous for. At the beginning of the film, Kirk and fellow retired Enterprise officers Chekov and Scotty are celebrity guests aboard the USS Enterprise-B on her maiden voyage. However, the ship responds to a distress signal from a transport ship engulfed in a mysterious energy ribbon. Undermanned and under-equipped though it is, the Enterprise-B - commanded by Captain John Harriman - answers the call and attempts to rescue as many passengers from the transport as it can, but is caught in the energy ribbon itself during the rescue. Kirk leaves the bridge and heads down to the ship's deflector control room in order to reconfigure the deflector array to emit a pulse that will push the ship away from the ribbon. Kirk is successful in this endeavour, but the deflector dish is struck by a discharge from the ribbon and the hull is breached. It is thought that Kirk was sucked out into space and perished.
Kirk was not killed, however, but rather misplaced from time. The energy ribbon that struck the Enterprise-B was in fact a doorway to another reality called the Nexus: a place where time has no meaning and those who dwell within it experience the most joyful fantasies they can imagine. This is where James Kirk found himself, living in his old house in the mountains with the love of his life. 78 years following his recorded death (though from his point of view he had only just arrived in the Nexus) Kirk was greeted by Jean-Luc Picard, captain of the USS Enterprise-D in the year 2371. Picard had entered the Nexus whilst trying to prevent El-Aurian scientist Dr. Tolian Soran from destroying a star and wiping out 230 million lives. He told Captain Kirk the truth about the Nexus and asked him to follow him back to his time to Veridian III to stop Soran. At first, Kirk responded selfishly and felt the galaxy owed him some peace after all he had done during his life in Starfleet. However, he reconsidered Picard's request after realising that nothing in the Nexus mattered, that it was all a mere fantasy.
Kirk chose to help Picard and joined him in returning to Veridian III, where the two legendary Enterprise captains fought Dr. Soran. Kirk fought with Soran on a bridge suspended over a rocky gorge and was left hanging on for dear life when the bridge's supports broke. Kirk held on for as long as he could, but he had managed to steal the control pad for Soran's trilithium probe launcher. He was able to decloak the launcher, allowing Picard to sabotage its launch controls. The bridge then gave way and Kirk fell into the ravine below.
Kirk managed to hold on until Captain Picard had destroyed the trilithium probe and Soran with it. Picard then knelt over the injured Kirk, thanking him for helping to make a difference one more time. Kirk replied "It was... fun." He then uttered "Oh my..." just as he slipped away. After Kirk's death, Captain Picard buried him beneath a mound of stones on the mountain.
In J.J. Abrams' reboot of the Star Trek franchise, James Kirk is portrayed by Chris Pine. In this alternate reality, the circumstances that led Kirk to his joining Starfleet and commanding the Enterprise are very different. He also suffers an earlier, though temporary, death which is seen in Star Trek Into Darkness.
In an epic role reversal of Spock's noble sacrifice in Star Trek II: The Wrath of Khan, Kirk risks his own life trying to save the Enterprise as it re-enters Earth's atmosphere. With the stabilization systems damaged and main power offline, the ship is set to meet fiery destruction until Kirk bravely enters the irradiated warp core chamber so that he can realign the core housings and restore power. He succeeds and the Enterprise is able to restabilize and avoid crashing, but Kirk is subjected to lethal levels of radiation and is seemingly killed.
However, Kirk's crew are able to revive their beloved captain after Spock succeeds in capturing the maniacal superhuman terrorist Khan. Using Khan's enhanced blood, Dr. McCoy gives Kirk a transfusion that restores him to perfect health.