Tyrion Lannister is a major character in the first, second, third, fourth and fifth seasons. He is played by starring cast member Peter Dinklage and debuts in the series premiere. Tyrion Lannister is the youngest son of Lord Tywin Lannister and younger brother of Cersei and Jaime Lannister. A dwarf, he uses his wit and intellect to overcome the prejudice he faces. Tyrion is falsely accused of the attempted assassination of Bran Stark and taken captive by Catelyn Stark. Though he is eventually released after a trial by combat, his arrest triggers conflict between the Lannisters and the Starks, which escalates into full war after the death of King Robert and the arrest and execution of Eddard Stark. Tyrion is shortly after sent by his father to King's Landing to be acting Hand of the King to his newly crowned nephew Joffrey, with instructions to rein him in. With him he takes a prostitute named Shae whom he makes his mistress and comes to love, and Bronn, a fearsome sellsword who serves as his bodyguard and enforcer. Under difficult conditions, Tyrion holds the city together, strengthens and organizes the city's defenses, and makes an alliance with House Martell. He plays a vital role in the Crown's victory over Stannis Baratheon's forces during the Battle of Blackwater, and is wounded. Afterwards, Tyrion loses his position as Hand to his father. He remains an important player in the court, however, and is appointed Master of Coin and unwillingly married to Sansa Stark, considered the heiress to the North after the scattering of the Starks. When Joffrey is poisoned at his wedding feast, Cersei accuses Tyrion of his murder and Tyrion is put on trial. Realizing that the trial is a farce, Tyrion demands a trial by combat. However, his champion, Prince Oberyn, is brutally murdered by the Crown's champion Gregor Clegane, sentencing him to death. Before the sentence can be carried out, Jaime frees him. A vengeful Tyrion kills Shae and his father, then flees with Varys.