Black Man (published as Thirteen in North America and later UK editions) is a 2007 science fiction novel by the British author Richard Morgan.

[1] Carl Marsalis is a selectively bred human ("genetic variant") known as a "Thirteen", characterized by high aggression and low sociability.

Carl, having won by lottery the right to return from Mars, works covertly, tracking down renegade Thirteens.

During a regular police investigation he becomes involved with a detective and begins to develop feelings for her, which beyond basic desires are unusual for a Thirteen.

Morgan's 2018 novel Thin Air is set in the same reality,[2] with another genetically-modified protagonist[2] but with all the action taking place on Mars.