Spoilers for the original Murderbot Diary All Systems Red abound. Consider yourself warned.
Following its emancipation at the end of the first book, Murderbot has decided to investigate its history, to see whether or not it committed a brutal rampage voluntarily or under coercion. To that end, it heads back to the mining facility detailed in its memory banks and begins to do a bit of digging around.
Of course, it needs a little help, both to traverse the great distances between colonies and to work out what on Earth is going on, now that it's been cut loose from its helper systems. Luckily, it happens to run into a scientific exploration vessel, who has a bit of free time during a routine crew-less cargo run, as well as a brain the size of a planet.
ART (the "Asshole Research Transport") is very interested in Murderbot's quest, being as it is both curious about interpersonal relationships, designed to create and control the perfect environment for its usual complement of crew, and lonely. It's also surprisingly susceptible to tales of human/ship camaraderie (they spend a lot of time watching Botflix together).
Which makes it an excellent voice in Murderbot's head performing an Oracle-adjacent function, though its puppy-like enthusiasm and general inexperience does provide the same sort of result you would expect if you googled "How to make friends". The chatty dialogue between these two about TV and the weird things humans do is definitely worth the price of admission.
Murderbot is increasingly humanised, acting for its own reasons and developing its own motivations, and the character growth is nice to see. I'm hoping for more of the same, though preferably not the full Bicentennial Man. The slightly off-kilter psychology is half the fun. To quote: "You may have noticed that for a terrifying Murderbot I fuck up a lot".
The emotional moments told in an unemotional manner are still a joy, and now we've got a few more sources of that. A particular source of comedy is a sexbot who pops in to say hello, who almost inevitably wants nothing more than "to kill all the humans".
It's a quick read, but a very enjoyable one. There's a reason the previous book got nominated for and won a lot of awards. Definitely one to have a look at. (Though start with the first if you've not read it already.)