What happens when a transporter malfunction goes beserk and splits Captain Kirk into two beings, one indecisive and the other a violent hell-bent lunatic with inappropriate desires for the lovely yeoman here played by Grace Lee Whitney?
The dark side of Captain Kirk runs amok aboard the U.S.S. Enterprise NCC 1701 and creates havoc for Sulu who is stuck with the landing party freezing on the planet surface. The Enemy Within does a brilliant science fiction twist on Robert Louis Stevenson's 'the Strange Case of Dr Jekyll and Mr Hyde' which is pure awesome.
Spock figures out that the 'Captain' requires both aspects of the 'Kirk personality' to function as a complete whole. Its really neat watching the good Kirk procrastinating over whether to allow Scotty and Spock use the transporter to restore him with his 'evil' twin.
Would you want to mind meld permanently with the EVIL Captain Kirk?
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