Pilot of the Rocinante and former MCRN officer. A Martian with a warm, garrulous personality that masks genuine melancholy about his failed family life. One of the finest pilots in human space, with an instinctive feel for orbital mechanics and ship handling.

Mechanic and general muscle aboard the Rocinante. A man who grew up in the worst conditions Baltimore had to offer and emerged without the capacity for moral judgment most people take for granted - he outsources that function to people he trusts. Straightforwardly violent when necessary, and deeply loyal to those he considers his people.

Former XO of the ice freighter Canterbury who becomes captain of the salvaged Martian gunship Rocinante after witnessing the destruction of his ship. A relentless idealist with a compulsion to broadcast the truth regardless of the political consequences, Holden repeatedly finds himself at the centre of events that define the course of human history.

Chief engineer and executive officer of the Rocinante. A Belter of exceptional intelligence and technical skill who carries a painful past involving the Free Navy. The moral conscience of the crew, she is also one of the most capable engineers in the solar system.

A high-ranking Martian military officer with a long-term strategic vision. A calculating and patient leader who positions himself to shape humanity's future beyond the Sol system.

A colonel in the Laconian Imperial Navy and former MCRN officer. One of the most capable and dangerous soldiers in the empire, assigned to hunt down Teresa Duarte and the underground resistance. Practical, professional, and entirely willing to do whatever the mission requires.

Martian marine gunnery sergeant who witnesses something on Ganymede that her government wants buried. One of the most physically formidable characters in the series, she is also one of its most principled - a soldier who cannot stop asking whether the orders she follows are worth following.

A Belter who rises from security chief at Tycho Station to captain of her own ship to president of the Transport Union. Pragmatic, loyal, and capable of enormous violence when the situation calls for it. One of the series' most consistent moral anchors in the later books.

UN Deputy Undersecretary of Executive Administration and one of the most powerful politicians on Earth. Foul-mouthed, brilliant, and utterly clear-eyed about how power works. She plays the long game better than almost anyone in the solar system and genuinely cares about the billions of people whose lives depend on her getting it right.

Daughter of the magnate Jules-Pierre Mao, who frames Holden for a terrorist attack in a misguided attempt to restore her family's honour. After her imprisonment she joins the Rocinante crew, carrying significant guilt and a body modified for violence she is trying to leave behind.

A scientist who travels to Ilus as part of a Royal Charter Energy survey team and becomes caught in the colony conflict. In the later books she becomes the Laconian Empire's leading expert on the alien gates and the entity that destroyed their builders - a role that places her at the centre of the series' most fundamental questions.

A geologist and scientist who joins the expedition to Ilus (New Terra). Good-humoured and easygoing, he provides a grounding presence among the research team studying the alien world.

A brilliant and amoral scientist formerly employed by Protogen. His expertise in protomolecule research makes him a valuable asset to whoever controls him, though his ethical boundaries are virtually nonexistent.

A young Laconian naval officer appointed to a position of authority. An earnest and disciplined military man who believes in the ideals of the Laconian Empire and the order it promises to bring.

Daughter of High Consul Winston Duarte, raised in the Laconian palace as the heir to an interstellar empire. Her friendship with a local boy and a strange alien-modified dog begin to pull her away from everything she has been taught to believe.