Khan is Khan Noonien Singh in the original Star Trek series, Star Trek II The Wrath of Khan, and Star Trek Into Darkness. Khan was one of a genetically enhanced / engineered "superhuman" race and one of the leaders of a rebellion in the Star Trek world in the late 20th century Eugenic Wars. Khan was thought to have controlled 1/4 of Earth's population. After their impending defeat, a group of 90 escaped and were unaccounted for ... until ...

In the 23rd century, the USS Enterprise came across a derelict ship, the SS Botany Bay, where Khan and his group had been in stasis. Once revived, they attempted to take over the Enterprise, but were defeated by Mr. Spock and Captain Kirk. Instead of executing Khan, or even turning him over to Starfleet, Kirk exiled Khan and his group, along with Lieutenant Marla McGivers, an Enterprise crew person who fell in love with Khan, Ceti Alpha V.

In Star Trek II:The Wrath of Khan, Starfleet makes a grave error while looking for a lifeless planet and stumbles across Khan on Ceti Alpha V (thinking it was Ceti Alpha VI). Khan takes over the USS Reliant and is obsessed with revenge against Kirk. He is ultimately defeated by the Enterprise.

In Star Trek Into Darkness, Khan of the alternate reality was spared after Doctor Leonard McCoy discovered that his blood could be used to revive Kirk, who was about to die. The alternate Khan was ultimately placed back in stasis with his crew.

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