Here, the entire population of a civilized planet surrenders to fear and anxiety when a woman claiming to be their Devil, Ardra, arrives to claim their souls in accordance with a thousand-year old contract. Ardra takes the form of Feklar, a Klingon devil...even though they aren't supposed to have one! Later, Ardra assumes the form of Satan with the stereotypical red skin, horns, etc. In the course of the episode, Picard exposes Ardra as a flim-flam artist, a woman playing on, again, primitive superstitions and beliefs.
Written by Johnny Byrne, the tale involved a once well-regarded alien scientist Balor (Byrne's play on the name of a demon, Baal) who has been "cast out" from his planet Pogron, because of his sadistic ways. Commander Koenig (Martin Landau) doesn't send Balor back to Hell, but he does kick the immortal being out of a nearby airlock, in a climax that forecast the last act of Alien (1979).
Although the series often featured human brands of evil in terms of serial killers, stand-out episodes such as "Lamentation" "Powers, Principalities, Thrones and Dominions," and "Somehow Satan Got Behind Me" suggested that demons were making mischief in the world of man, spurring him on to greater evils ("Room with No View").
"Lamentation" introduces the quite-possibly demonic Lucy Butler (Sarah-Jane Redmond) to the series, and Lucy captures both our revulsion at and attraction to Evil. She is a seducer, a temptress...and an absolute monster, one of television's all-time classic characters. Lucy reminds us that the Devil isn't always a beast...but sometimes, and terrifyingly, a beauty.