The narrative begins as Lucius journeys into Thessaly, a region famed for witchcraft, where his obsession with magic leads him to seek out a powerful enchantment through his lover Fotis. A tragic mistake during the ritual transforms him not into a bird, but into a beast of burden. Trapped in an asinine shape with his human consciousness fully intact, he must endure a series of brutal owners, ranging from thieving bandits and abusive millers to fraudulent priests and a violent boy. Along the way, he overhears various embedded tales and folktales, most notably the elaborate mythological romance of Cupid and Psyche, which mirrors his own themes of curiosity, forbidden knowledge, and trials.
Throughout his endless tribulations, he hopes to find healing roses to restore his human form, observing firsthand the cruelty, greed, and folly that govern human interactions. The novel provides a satirical and deeply human look at ancient life through the innocent eyes of a suffering animal. The resolution shifts tone completely as divine intervention finally brings salvation, leading him toward a profound spiritual awakening and redemption.