By Martha Wells
Tom Doherty Associates, 2020
Network Effect is the fifth Murderbot book, but the first full novel. It is a continuation of the Murderbot Diaries, and differs from the earlier stories only in length. This is a great series, and you should read it -- starting at the beginning. The first novella in the series is All Systems Red. If you start with Network Effect you will be missing a lot of context, but will not be completely lost; but seriously, why not read things in order? The remainder of this review contains mild spoilers for the earlier books, but nothing too serious.
Murderbot is still working for Preservation (Dr. Mensah's group), taking care of any hostiles that might bother survey teams. This is fairly simple, run-of-the-mill stuff for a SecUnit... until the survey ship it is protecting gets attacked and dragged into a wormhole for no apparent reason. It quickly becomes apparent that they have been kidnapped by something not-quite-human, which seems to think that Murderbot has access to a powerful weapon, and are holding some of Murderbot's "friends" hostage until it is produced. And also, it has the friends of the "friends". And also a corporation explorer ship, and also a planet. There are a lot of hostages.
This novel primarily expands on the previous works by having Murderbot become part of a team -- or teams -- and have to deal with a lot of humans being human and non-humans being non-human. ART makes an appearance, and so does a friendly (okay, "friendly") SecUnit. It would be an exaggeration to say that Murderbot coordinates the troops to save the day, but it does tolerate them while accepting some assistance in day-saving.
The stories ends with good potential for further sequels, and in fact a follow-up novella (yep, we're back to novellas) is planned for 2021 -- Fugitive Telemetry.