The Enemy Within
A magnetic ore causes a transporter malfunction which splits Captain Kirk into two people, one meek, and the other an agresssive wild man. The landing party, headed by Sulu is stranded on the planet's surface in ever decreasing temperature until the transporter can be fixed.
Guest Cast:
Mudd's Women
After a highspeed chase, the captain of a scout vessel, Harry Mudd, conman, and his cargo, three beautiful women are rescued and brought aboard the Enterprise. Mudd complicates matters by making a deal with some dilithium miners to trade the girls for the dilithium the Enterprise needs to repair her engines.
Guest Cast:
What are Little Girls Made Of?
Nurse Chapel plans to be reunited with her lost love, Dr. Roger Korby. Instead, they find that Korby has discovered android construction technology, and plans to use it to take over the federation. His attempt to replace Kirk with an android failed when Kirk was able to implant a message to Spock in the androids memory. At the end, it is revealed that Korby too is an android.
Guest Cast:
Miri
The Enterprise crew discover an Earthlike planet where all of the adults were destroyed by a virus which was intended to prolong life. It prolonged the life of the children, but once they reached puberity, the disease killed them as well. The landing party is infected by this disease, and they must come up with a cure before they all die. And they also must deal with the undisciplined children who are very distrustful of adults.
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