In a near future ravaged by environmental disasters, people are able to join their consciousness with others into new, multi-bodied selves, with their previously individual bodies as mortal avatars, or “drives,” through which the theoretically-immortal “join” can act upon the world. The technology that allows this is not well-understood, though, and the implications for humankind are fraught.

“Join” is full of fascinating ideas about personhood, mortality, conscience, and morality, hung on a fast-paced plot framework that at times reminded me of noir fiction in the tradition of Jim Thompson and James M. Cain. The denouement felt a little rushed–having set up a powerful philosophical conundrum in the first 200 pages, the story is brought to a close with two sharp and violent scenes in the last twenty pages–but the density of the ideas presented make up for the abrupt conclusion.