We start off on a desolate alien planet being explored by a group of scientists called the Preservation led by Dr. Mensah. Protecting them from the hostile fauna of the planet is a SecUnit named Murderbot. What the humans do not realize is that the Murderbot has a faulty governor module, essentially meaning that it has started to think for itself. The expedition starts discovering anomalies in the survey maps of the planet, the satellite connection goes silent and the second expedition on the planet DeltFall is unresponsive. When they travel over to the DeltFall site, they discover that all humans have been killed and are attacked by their SecUnits. This is when they realize that there is a malicious third expedition on the planet who have discovered something valuable and are ready to kill everyone else to profit from it.
This was a fast and short read, and can easily be finished in one sitting. Wells succeeds in creating sci-fi-lite, just enough interesting details to keep the story intelligent. The novella is narrated by Murderbot and at the end of the book it gets its freedom from Dr. Mensah and chooses to roam free among planets.