Doctor Vosill's young apprentice and assistant, and the first-person narrator of the Doctor chapters. An orphan of Koetic parents killed during the Imperial sacking of Derla, he was raised among officers' orphans. Devoted to Vosill, he secretly reports on her to Guard Commander Adlain - the unnamed "Master" the apprentice addresses in his journal.

The Guard Commander of Haspide and the unnamed "Master" to whom Oelph addresses his reports - it is Adlain who has set the apprentice to spy on Doctor Vosill and account for her every word and movement. Pragmatic and politically astute, he navigates the cramped space between protecting the King and managing the court's scheming nobles, and treats Oelph with a brisk, watchful seriousness that the apprentice never quite knows how to read.

An elderly, watchful Duke at King Quience's court, possessed of a sharp mind, an unhurried manner, and a deep-rooted suspicion of the King's foreign-born physician. Where the younger nobles dismiss Doctor Vosill as a curiosity, Walen treats her presence near the throne as a problem requiring patient, methodical attention - the kind of attention an old man with influence, time, and few scruples can bring quietly to bear.

The Duke of the province that contains the summer palace of Yvenir, where King Quience's court repairs each year to escape the heat of the capital. Extravagant in his entertainments and unmistakably pleased with himself, Quettil makes an art of receiving royalty: there is always a new feast, a new diversion, a new piece of stagecraft prepared for the King's eye. Doctor Vosill is one of the few figures at court he treats with open dismissiveness, his courtesy stiffening into hostility whenever her foreign manners and unconventional medicine intrude on what he considers a properly ordered occasion.

A lanky, slightly stooped, conspicuously kind-hearted Duke, and the man who employed Vosill as a household physician before her abilities drew the attention of the King and she was taken into the royal service. Ormin is among the most enthusiastic supporters of Quience's progressive reforms, the first nobleman to volunteer his own province as a testing ground for the civic changes the more cautious dukes find alarming - the rare figure at court whose decency seems almost an embarrassment to the harder players around him.

A young, thin, sallow Duke who comes into his title abruptly on his father's death and arrives at court still visibly working out what kind of nobleman he intends to be. Through the long summer at Yvenir, Ulresile sheds some of his initial callowness for a louder, more opinionated manner, and develops an undisguised, slightly hapless infatuation with the King's foreign physician - turning up wherever Doctor Vosill is likely to be, presenting her with carefully chosen gifts she equally carefully declines, and quietly accumulating the kind of public embarrassment he is too young and too pleased with himself to recognise as such.

Chief torturer to King Quience; murdered at Yvenir Palace in a case the doctor Vosill solves from his wounds before being herself accused.

Assistant to Nolieti, the King's chief torturer - a filthy, shifty, perpetually-looking-sideways fellow whose duties keep him in the unloved corners of the palace cellars where the questioner's work is done. Unoure makes his on-page appearance as the figure sent up to escort the Doctor down to those rooms, an errand he performs with a leering kind of pleasure that the Doctor, Oelph, and almost everyone else who has cause to deal with him would rather not be reminded of.

Duke Quettil's chief torturer at Yvenir - a small, barrel-shaped man who wears, as his most arresting affectation, a set of teeth filed from those he has extracted from the people he has questioned, fitted in place of his own. Ralinge takes an unmistakably sinister interest in Doctor Vosill from the moment he becomes aware of her: appraising her in the corridors, finding excuses to be present where she is, conducting himself with the unhurried patience of a man whose work has accustomed him to the idea that he is eventually permitted to do whatever he wants with whoever is brought before him.

Personal physician to Duke Quettil at Yvenir - a small man with a sneering manner and a settled conviction that the proper way to practise medicine is the way he has always practised it, ideally with as little reference as possible to whatever it is the King's foreign physician thinks she is doing. Skelim treats Doctor Vosill with open hostility from the moment she sets foot in his employer's province, dismissing her forensic instincts as theatrical, her unfamiliar techniques as suspect, and her foreign medical terminology as an affectation he can grudgingly reproduce when professionally cornered but evidently finds personally distasteful.