Altered Carbon is the first book in a Cyberpunk trilogy (often called either the Altered Carbon series or the Takeshi Kovacs series) by British writer Richard K Morgan. The series takes place some 500 years into the future, in the UN Protectorate, a totalitarian government spread over several different planets that enforces its rule with the use of 'Envoys'; mentally-conditioned Shock Troopers who specialise in covert deployment and bringing down rebel governments.