Adam Roberts 
Stone 

Sprung from a prison in the centre of a star, the universe’s last criminal is employed to kill the population of a planet. It is a crime that will tear apart an interstellar utopia. Keeping ahead of detection and preparing the crime, the killer voyages to numerous worlds and hones the instincts required for murder. And wonders who is behind the contract.Roberts’ new novel is an extraordinary fusing of ideas, exotic locations, personal drama and an enquiry into the nature of crime in a society that thinks it has forgotten how to commit it.