I heard Diane Duane talk about this book on a podcast years ago, and she made it sound so compelling it's been on my radar ever since, even though I have never watched a single episode of Star Trek's original series. I went online recently to see if it was available as audiobook, and found a fan-made one which was posted chapter by chapter to youtube during 2020! Three friends decided that recording this book would be their covid project, and apparently Diane Duane retweeted several of their posts about it. I don't know if that counts as official authorization, but at the very least she was aware of the project and looked favorably on it.

The story itself is quite enjoyable. It opens with Captain Kirk's Enterprise being awarded the chance to test out a new engine system, the Intergalactic Inversion Drive, which far outstrips the warp drive in instantaneous jump capabilities. The Enterprise ends up hosting the alien scientist who invented it, an original character created by Duane who stole every scene she was in. This Inversion Drive pulls energy from an infinitely dense particle, but as the crew soon discovers, using it can have catastrophic effects on matter, time, and space near the ship. The ordeal that the crew must go through to heal the effects of the Inversion Drive is deeply philosophical and genuinely moving. I was already a long-time fan of Duane's Young Wizards series, but I'm definitely interested in reading more of her Star Trek novels after this.