Rogue Protocol and Exit Strategy, by Martha Wells

In Murderbot 3 the independent SecUnit goes in search of evidence against the evil GrayCris company, allying with and protecting a new group of humans and learning a lot about the potential of human relationships along the way. The fourth and concluding novella in the Murderbot series sees the rogue SecUnit on a rescue mission to save Dr Mensah, its mentor and possible friend from the first story, who has been kidnapped by the GreyCris corporation. A satisfying journey arc is completed with trademark humour and humanity.