The gentle, pleasure-loving people of Argelius II, whose society had so thoroughly given up violence and jealousy that a series of murders blamed on Montgomery Scott left them almost helpless to respond.
The Argelians appear in the Original Series episode Wolf in the Fold. Some two centuries before the Enterprise's visit their world went through what they call the Great Awakening, after which the people devoted themselves to love and pleasure. Jealousy is regarded as distasteful and crime is almost unknown.
Because Argelians have little taste for administration, they hire outsiders to run things; the city's chief administrator, Hengist, comes from Rigel IV. The planet is also a valued port of call for Starfleet crews.
When a dancer named Kara and two other women are stabbed to death in 2267, suspicion falls on Scott. Prefect Jaris turns to an old custom, the empathic contact practised by his wife Sybo, a priestess. The inquiry finally exposes the killer as an ancient bodiless entity that feeds on fear and was once known on Earth as Jack the Ripper.