In a corporate-dominated spacefaring future, planetary missions must be approved and supplied by the Company. Exploratory teams are accompanied by Company-supplied security androids, for their own safety. But in a society where contracts are awarded to the lowest bidder, safety isn't a primary concern. On a distant planet, a team of scientists are conducting surface tests, shadowed by their Company-supplied 'droid--a self-aware SecUnit that has hacked its own governor module, and refers to itself (though never out loud) as 'Murderbot'..
