the story: The ship temporarily houses alien convicts.
what it's all about: "Repentance" is basically the Dead Man Walking of Star Trek episodes. It's not really about a member of the crew at all, but the guest character played by Jeff Kober, a convict who undergoes an operation that cure him of the impulses that led him to murder, but leaves him with unbearable remorse. The family of his victim has a chance to grant him an appeal, based on this development, but ultimately chooses against it. It works as a tragedy, whether or not the viewer carries the idea into the real world, and that's all due to Kober's sympathetic performance.
There's other shenanigans going on around this plot, including a formulaic fellow convict played by F.J. Rio (playing a far less sympathetic character, certainly compared to the last time we saw him, in Deep Space Nine), basically padding. Seven is loosely tied into the plot, a Borg parallel concerning her lingering guilt over her actions while a drone, but it's not terribly memorable.
What "Repentance" does is affirm the strength of Star Trek's original episodic mandate, in a way Voyager had in particular come to master, so that guest characters were capable of carrying whole hours, as in the masterful "Distant Origin." This one's comparatively minor, but as a late addition in the final season, it's a great reminder of what Voyager was capable of, regardless of persistent fan criticism to the contrary.
- franchise - A testament to Star Trek's original episodic format.
- series - And how Voyager could so masterfully employ it.
character- A weak effort to tie Seven into the plot.
- essential - A compelling guest character effortlessly sells his own case.