After attacking an outpost, Romulans battle the Enterprise.
Spock undergoes the Vulcan mating ceremony.
Hogan convinces Kommandant Klink that the heavy water being stored at Stalag 13 is a youth potion.
A small insurance company retains Perry Mason to look into a mysterious outbreak of apparent heart attacks.
The only survivor of a series of knifings of prostitutes leads Stone and Keller to the murderer; guest James Olson.