Society is no comfort To one not sociable."
King Cymbeline’s daughter Imogen secretly marries a lowborn man Posthumus instead of Cloten, the king’s stepson. Cymbeline immediately exiles Posthumus to Italy where he meets the soldier Iachimo, who wagers he can seduce Imogen. He hides inside a chest in her bedroom, and steals a bracelet while she’s sleeping. Iachimo uses the bracelet as proof of his conquest, also offering intimate details about Imogen’s body. Posthumus engages his servant Pisanio to murder the “unfaithful” Imogen.
Instead, Pisanio warns Imogen and convinces her to disguise herself as a boy, but tells Posthumus she is dead. Imogen goes to Wales, where she encounters Belarius and his adopted sons, who are actually Imogen’s own brothers Guiderius and Arviragus. When he was banished twenty years earlier by Cymbeline, Belarius kidnapped the boys to prevent heirs to the throne.
Cloten has pursued Imogen to Wales, where he’s killed in a duel with Guiderius. Imogen drinks a potion that the queen intended to poison her, but it only sends her into a deep sleep resembling death. Belarius’ sons lay her body next to Cloten’s, which she mistakes for the slain body of Posthumus when she awakes. Becoming despondent, she stays in disguise and joins the Roman army as a page.
In the battle between the Roman and British armies, Posthumus and Iachimo travel with the Romans but Posthumus disguises himself as a peasant and fights for Britain. The Romans are defeated but Posthumus, still in despair over having ordered Imogen’s death, gives himself up as a prisoner. When Cymbeline brings the prisoners before him, he sets all confusion straight: Imogen is reunited with Posthumus, Iachimo is forgiven, Belarius is pardoned, and his adoptive sons’ identities are revealed. The court doctor brings news that the queen is dead, having confessed her evil plot to kill Imogen and Cymbeline so that her son, Cloten, would become king.
Cymbeline gives an oration to the gods and announces peace between Britain and Rome.