The first main character, Palinor, is found washed up on a beach, near dead and with no forms of identification or proof that he is who he says he is, an elected Prince of a foreign land. No one from Grandinsula has heard of this country, and it is soon learned he does not believe in God, an offense punishable by death. It falls to the Cardinal Prince of Grandinsula to convince Palinor to convert, and he delegates this task to the loyal Church scholar Beneditx. Beneditx has many theological conversations with Palinor, yet fails to convince him to convert (and, in fact, ends up suffering from a Crisis of Faith himself).
The other side of the story, with Amara, focuses on how a group of nuns hope to raise her to become 'human', and yet keep her ignorant of God, so as to see whether knowledge of God is innate or learned — a plan orchestrated by Severo, as, if it can be proved that humans are not born with knowledge of God, then Palinor will not be held guilty of rejecting God — rejection can be punished, ignorance cannot be. However, though early tests with Amara would suggest knowledge is learned, she is later coached by the nun caring for her to proclaim belief in God, so she will be let go rather than kept confined waiting to see if she finds it by herself. Thus it is left unclear as to whether this knowledge really is innate or not, although Amara shows no signs of it before this.
Either way, the Church authority uses this as proof of Palinor's sin, and puts him to death for heresy.
It's on the A level syllabus.
Contains examples of the following tropes:
- As the Good Book Says...: Used by the religious side of the main debates between Beneditx and Palinor, along with 'As Thomas Aquinas Says'.
- As You Know: The Inquisitor reminds Severo the Inquisition's authority overreaches that of the local cardinal where heresy is concerned, something Severo retorts he already knows.
- Author Tract: The entire book is one of these about theism and atheism, set as a story.
- Crisis of Faith: Beneditx has one after talking with Palinor, and becoming convinced by Palinor's atheist retorts.
- Deliberate Values Dissonance: The values of Renaissance Christians are ably demonstrated for the reader, such as the far more powerful role of religion in people's lives, to the point of harsh persecution toward dissidents. Additionally, the Christian characters find Palinor's view hard to fathom (as indeed real Christians would have at the time). The Inquisitor finds the idea of religious tolerance, as Palinor describes in his homeland, appalling.
- Despair Event Horizon: Beneditx reaches this after he becomes convinced by Palinor that God does not exist.
- Downer Ending: Palinor is killed, Beneditx has become a broken man, Severo is full of regret over Palinor's death, Amara has gone off to live a life of isolation, and an Aclaran fleet is coming to punish the island for Palinor's death.
- Easy Evangelism: Averted by how set Palinor is in his beliefs (or lack thereof), making Beneditx's job of converting him impossible. Palinor outright states he cannot be convinced.
- Elective Monarchy: Palinor is an elected prince of his home country, Aclar.
- The Fundamentalist: The Inquisitor, unsurprisingly. Severo hoped he might be corrupt (as many Inquisitors were reputed to be) and thus they could buy him off. However, he's soon shown that the man is a true believer.
- Heel–Faith Turn: Beneditx was hoping to cause one in Palinor, though Palinor wasn't a Heel to begin with (the Church saw Palinor as evil for disbelief in God, and so Beneditx was hoping that, by converting Palinor, the Church would see him as good and spare him). Instead this backfires on him, since Palinor's superior retorts lead him to undergo a Crisis of Faith from which he never recovers.
- Hollywood Atheist: Discussed. Palinor does not fit the stereotypes, surprising the Christian characters, who believe an atheist has no reason to be moral.
- Honor Before Reason: Palinor refuses to pretend he's repented his atheism even when the cost would be death, saying he would lose his integrity.
- I'm a Man; I Can't Help It: This is used by one character to defend some shepherds gang-raping a twelve-year-old girl, because of the fact she'd been running around naked and they hadn't seen females in a long time.
- Karma Houdini: Although the abbess curses them, she doesn't inform the authorities of the shepherds raping Amara, and they're never punished or even arrested.
- Kill It with Fire: At the close of the book, Palinor is burned at the stake by the Inquisition for heresy.
- Mercy Kill: Palinor is killed with a material that emits deadly yet painless fumes to spare him from being burned alive.
- My God, What Have I Done?: Severo reacts this way after he realizes what is going to happen with Palinor after he turned him over to the Inquisition.
- The Philosopher: Beneditx and Palinor. Also oft-mentioned is Thomas Aquinas, a real example.
- Questionable Consent: Palinor orders his female servant Dolca to undress. Dolca obeys and is described as being fearful though he says that she can refuse sex with him. She doesn't, and he has sex with her (but doesn't stop it despite knowing this hurts her). Then, after his male servant Joffre (her sweetheart) comes in, he suggests that they have sex together while he's watching, and the pair agree. After this, he has sex with Joffre, then guides Joffre into having sex with him in turn. Given they are his servants and used to obedience, plus the rest, this does not come off very well.
- Raised by Wolves: Amara was raised by a wolf along with her sister after both were abandoned at birth. She's discovered by the people of the island where from years later, then put in a convent. She grows up slowly from being a wild child but is never fully at home in human society, choosing a semi-solitary job later.
- Rape as Drama: Amara is caught and gang-raped by shepherds when she runs away from the convent.
- Sex Starts, Story Stops: About two-thirds of the way through the book, Palinor has a threesome with his (female and male) servants, which comes up quite unexpectedly while adding nothing to the plot. It also paints him in a somewhat bad light, given the questionable consent on their part as they're dependent on him for livelihood and used to obeying his orders.
- The Soulsaver: Beneditx (and Severo) try to be this for Palinor.
- The Theocracy: Grandinsula is one. Severo (the Cardinal) is also Prince, due to his father and older brother dying so that he inherited the position. The Catholic Church is thus also the state religion, with Jews and Saracens (Muslims) relegated to special city quarters and atheism banned (however, this was the case even for countries where the clergy didn't rule then).
- A Threesome Is Hot: Palinor gets both his male and female servants to have sex with him, plus each other as he watches them.
- Unwitting Pawn: Amara is one in Severo's plan to see if knowledge of God is innate or learned, and while Severo is not the villain, the plan ends up causing Palinor to be executed.
- Will Not Tell a Lie: Palinor refuses to lie, even when his life is on the line, saying it would demean him.
- Wild Child: Amara, raised by wolves from a young age, is one (and is actually based off of a real-life feral child found in France).