Lazarus
Lazarus was an eccentric scientist who also claimed to be a time traveler from the distant past. Lazarus suffered from extreme paranoia and mental illness, a result of his knowledge of an antimatter universe which was identical in all respects to the normal universe, yet comprised of "minus" energy consisting of antimatter.

Pursuit of counterpart 

At some point in the past, an advanced civilization discovered the existence of an alternative warp and proved that an identical universe existed on another dimensional plane. Lazarus learned that a counterpart of himself existed in this anti-universe, and the knowledge drove him insane. Lazarus invented an elaborate paranoid delusion, where his counterpart from the other universe was in fact a murdering creature, a beast, and a "terrible thing". Lazarus convinced himself that his nemesis had in fact destroyed his civilization and Lazarus vowed a holy mission to kill his counterpart.

It was also known to Lazarus that to come into contact with his counterpart would bring their identical particles of matter and antimatter together. The resulting confrontation would create an annihilation type event which would destroy both universes. In his mental state, this meant nothing to Lazarus, as his counterpart would later explain:

"He could not live knowing that I lived. He became obsessed with the idea of destroying me. And the fact that it meant his own destruction... and everything else... meant nothing to him."

By the time Lazarus had gone insane, he had invented or acquired a ship which had the ability to breach the negative magnetic corridor that connected the two universes. When Kirk confronted Lazarus regarding there being no planet at the location Lazarus claimed to be from Lazarus then claimed his ship was a "time chamber, a timeship" and that he had only traveled through time not space. ()

Meeting the Enterprise 

In 2267, Lazarus's ship appeared on a barren desert world after he had pursued his counterpart (the anti-Lazarus) across space and time. Just prior to his arrival, Lazarus had entered the corridor between the two universes – an action which caused a massive spatial disruption which in turn drew the attention of Starfleet.

Assigned to investigate, Captain Kirk and the  located Lazarus on the surface of the desert planet. Lazarus relayed his story of the murdering beast like creature, claiming to have escaped the destruction of his civilization through sheer luck as he was inspecting magnetic communication satellites when "the Thing" had murdered his entire civilization.

Lazarus's story began to fall apart after further investigation by Captain Kirk and Lazarus was confronted several times to explain the true nature behind the phenomena which had struck the universe and also the truth behind Lazarus' nemesis "the Thing". Lazarus responded with more lies, then demanded Kirk provide him with dilithium crystals to destroy his nemesis. When Kirk refused, the crystals were soon stolen; although by this time, Kirk and Spock had realized there were two versions of Lazarus. ()

Final confrontation 

In a final confrontation, Kirk was accidentally transported to the antimatter universe, where anti-Lazarus revealed the whole story. He confirmed that if Lazarus succeeded in crossing over to the antimatter universe, and there confronted anti-Lazarus, the result would be the destruction of both universes.

Together, Kirk and anti-Lazarus forced Lazarus into the negative magnetic corridor that connected the two universes. Kirk then destroyed Lazarus' spaceship, which also destroyed anti-Lazarus' ship, sealing the corridor, saving the universes – and trapping both versions of Lazarus together for the rest of time. ()

Appendices

Memorable quotes 
"He's humanoid...outside. But inside, he's a hideous murdering monster!"

"Then you'll join me in my holy cause! Help me in visiting justice and vengeance upon him!"

"He's death! Anti-life! He lives to destroy!!"

"Run! Run! It'll do you no good! I'll chase you into the very fires of Hell!"

Background information 
Lazarus was portrayed by actor Robert Brown. According to the , the episode's script refers to the Lazarus from our universe as "Lazarus-A," and the Lazarus from the antimatter universe as "Lazarus-B." () However, at least one revision of the script refers to them as "Lazarus #1" and "Lazarus #2", respectively.

Lazarus was one candidate rumored to possibly be an antagonist in the film . Before the movie was released, a name for the villain was revealed to be "John Harrison", though whether this was his actual name or merely an alias was undisclosed. , in the lead-up to the film's release, speculated a 35% probability that the character would turn out to be Lazarus. Ultimately, "Harrison" turned out to be Khan Noonien Singh.

External link 
 

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