It’s an acting exercise for Jeri Ryan! Which is great, but the plot itself is pretty thin, though it does give us some great moments with, not just Seven, but also Tuvok and Naomi. The Star Trek: Voyager Rewatch suffers through an “Infinite Regress.”
Oftentimes, a science fiction show will do an episode whose express purpose is to be an acting exercise for one of the stars—or several, in the case of the inevitable body-switching episode that so many genre shows do. In the case of the person-gets-personalities-downloaded-into-them trope, TNG did it with Data in “Masks,” and Stargate SG-1 dipped into that well twice with Daniel Jackson, in “Legacy” and “Lifeboat,” and we get it again here.
Mind you, Jeri Ryan is very much up to the task. She’s an amazingly chameleonic actor, which has only become more evident as she’s continued in her career (and arguably put to best use during her time on Leverage playing a grifter), and she’s just superb here. My favorite is her Ferengi, which is especially hilarious, but she’s equally convincing as a little kid, as a Vulcan, and as a Klingon.