Richard is an unattractive man with a hunchback whom Shakespeare describes as "rudely stamp'd," "deformed," and "unfinish'd." The first scene finds him lamenting his brother's ascension to the throne and his nephew's succession before his own. He plots to remove his brother Clarence, ahead of him in succession, and frame him for a crime that will place him in the tower of London.
Richard makes it clear he has committed many terrible acts, and intends to commit many more. He sets his sights on Lady Anne, the widow of the Prince of Whales. He persuades her to marry him through his persistence, without her knowing that he is the killer who made her a widow.
Richard also helps to create a hostile environment at court, by creating drama between all the noble parties. Richard plots to have his brother Clarence killed in the tower. Simultaneously his brother has recalled a vivid dream he had that seems to portray Richard as a mass murdering psychopath. Clarence is later killed by murderers that Richard planted within the tower.
With his brother Clarence's sudden death, Richard brings stress to his brother, King Edward, bringing on an illness and his death. He suggests his wife is behind Clarence's execution. When his brother dies, he also kills his wife's confidante Lord Rivers, leaving the widowed queen completely alone.
With funeral arrangements underway, Richard meets his nephew, Edward V, and several Lords from his widow's side of the family. Richard orders the Lords arrest and later beheading. The young prince Edward V and his even younger brother prove to be an intellectual challenge for Richard, openly mocking and outsmarting him.
Richard, worried again about conflicts in his ascension, has both of the princes killed. He decides to woo Edward next remaining heir, his own niece, and kills Lady Anne so as to remove any conflict there. As the family mourns the princes deaths, Richard asks Queen Elizabeth in help for her daughter's hand. But the Queen is not impressed with Richard's tone and tells him she will let him know in due time.
Richard becomes increasingly paranoid and loses favor amongst nobles in court. Lord Buckingham and then Richmond attempt to lead rebellions against him, and he has them both executed. All sides arrive for battle at Bosworth Field, but Richard is visited beforehand by the apparitions he has murdered, telling him to "Despair and die!" He wakes screaming and alone, and realizes how his terrible behavior has isolated him in the world completely.
During the battle at Bosworth Field, Lord Stanley (also Richmond's stepfather) leave Richard to fight on his own. They will no longer stand at his side. Richard is infuriated and calls for Lord Stanley's son, George Stanley, to be executed. Since they are in the heat of battle, this command is not followed and Richard is left at a disadvantage within the narrative for the first time.
After he is thrown from his horse in the field, he famously calls out for "A horse, a horse, my kingdom for a horse!" His calls go unanswered, and Richmond kills Richard in their final battle. This leaves Richmond to ascend to the throne, named Henry VII, and marry the Princess Elizabeth.