Henoch

"You see, Sargon would not permit me to keep this body. It is therefore necessary for you to kill your captain, so that Sargon will die with him."

- Henoch, to Nurse Chapel

Henoch is a one-shot villain from the Star Trek franchise, appearing in the Star Trek: The Original Series episode "Return to Tomorrow."

He is played by the late Leonard Nimoy, who also played Mr. Hyde in The Pagemaster, Master Xehanort in Kingdom Hearts, and Sentinel Prime in Transformers: Dark of the Moon.

Henoch is one of three survivors of an ancient, long-dead race. In 2268, his preserved consciousness, along with those of Sargon and Thalassa, is discovered by the crew of the USS Enterprise (NCC-1701) commanded by Captain James T. Kirk. While Sargon possesses Kirk and Thalassa, his lover, possesses Dr. Ann Mulhall, Henoch possesses the body of Commander Spock, and he revels in his host's superior Vulcan physiology.

Sargon and Thalassa possessing Kirk and Mulhall for long periods of times causes strain upon their bodies, so Henoch (whose host can house him for longer) develops a formula that allows Sargon and Thalassa to counterbalance this effect long enough for them to build robotic bodies for themselves. However, eager to retain his Vulcan body (believing Sargon will not allow him to remain in Spock's body), Henoch hypnotizes Nurse Christine Chapel into loading a formula that will kill Kirk and therefore Sargon.

Later, Henoch tries to entice Thalassa into keeping her own human body, and destroys the orb housing Spock's consciousness. He then takes over the Enterprise's bridge, wreaking havoc upon the bridge crew. Kirk, Mulhall, and Dr. Leonard McCoy arrive to stop him, but he incapacitates Kirk and Mulhall. McCoy then advances on Henoch, who stops him and boasts that he knows every thought of every mind around him. Henoch then orders Chapel to take McCoy's hypospray, which contains a formula meant to kill him (Henoch), and inject him with it, but Chapel injects the formula into Henoch instead.

Henoch jumps up from the captain's chair, shocked, but he turns to the crew and claims he will just find another body to inhabit. He then looks fearful and begins begging Sargon to allow him to transfer, but he falls dead.

It then turns out that Spock's consciousness was within Chapel the whole time, and that Sargon allowed Henoch to believe that the formula he was injected with was deadly to him so he could trick him into vacating Spock's body.

Quotes
"Must I make an example out of you, helm?"

- To Sulu when he attempts to stop him on the bridge

"Fortunately, Doctor, I know every thought of every mind around me."

- To McCoy when he tries to inject him with a lethal concoction

"Fools! I will simply transfer to another place, another body. ... Sargon! No, Sargon, please! Let me...let me...transfer..."

- Henoch's last words