Guiderius, known as Polydore, is Cymbeline’s eldest son, but is unaware of this fact as he was kidnapped at the age of three by Belarius and brought up by him as a hunter in a cave along with his younger brother Arviragus.
Twenty years later, he is growing irritated by his lack of formal education and wishes to know what the real world is like. A great hunter, he longs to have a chance to be a great soldier as well. He feels an immediate sympathy for the boy Fidele and is excessively fond of him; He is heart-broken at the boy’s death, but delighted to later discover that firstly, he’s still alive and secondly, he’s actually their sister Imogen. Quite blunt, he does not take kindly to insults and has no qualms about cutting off Cloten’s head. Hearing of the Roman invasion, he insists on going to fight it, with or without Belarius’s permission, and greatly distinguishes himself in the fight, saving Cymbeline’s life with the help of his brother and supposed father as well as turning the fleeing Britons back to the fight. He refuses to apologize for killing Cloten and is only saved from death himself by being revealed as the King’s son. He has a mole on the back of his neck.