the story: Lwaxana Troi serves as the voice of reason as she argues for an elderly man's right to live.
similar to: Star Trek II: The Wrath of Khan
my thoughts: Just as "The Nth Degree" a few episodes earlier used Barclay, "Half a Life" ingeniously uses Lwaxana Troi in strict contradiction to her established character diameters. Previously known at best as a comedic presence and at worst a pest, Lwaxana would not have been considered worth taking seriously at any rate. (For another such instance, witness Deep Space Nine's "The Forsaken.")
Just as Kirk felt old and pointless in the first and second movies, this episode tackles the matter of what aging members of society can still contribute. As is usual for the franchise, it presents an extreme example, literally an alien culture that condemns the elderly to death (a few years ahead of the Jack Kevorkian debate in the real world), and is one of the best examples of topical subject matter in the franchise, one of the more positive tropes and frequently the source of its best material.
And for a change, the voice of the opposition, the poor man at the center of the story's own daughter, doesn't come off as stilted, possibly because it's Michelle Forbes' first franchise appearance. She'd inhabit the more familiar guise of Ro Laren next season.
But it's really Lwaxana's moment to shine, and it's so unexpected and it works so unexpectedly well, that it's easy to take for granted, but it deserves to be remembered as a classic.
criteria analysis: franchise - series - character - essential (all criteria met)
Majel Roddenberry (Lwaxana)
David Ogden Stiers
Colm Meaney (O'Brien)
Carel Struycken (Mr. Homn)