The play opens with Richard III declaring that all in England is well, except with himself. Richard III convinces Edward
IV to send his own brother Clarence to jail because his name starts with a G (George, Duke of Clarence). Hastings is released from prison. Richard III visits the sickly King Edward IV. On the way, he meets Anne Neville, who is transferring Henry VI's body to his funeral. They fight over the royals' deaths. Richard III tells Anne that he killed them because he loves her. He even gets her to like him. At the London palace Queen
Elizabeth informs Rivers and Grey that Richard III would be the protector if Edward IV dies. Richard III enters and fights with Queen Elizabeth about his loyalties and intentions. Queen Margaret shows up and curses Edward IV to die of sickness; Edward V to die young; Queen Elizabeth to live long, and be not wife, mother, or Queen; Rivers, Dorset, and Hastings to die an unnatural death; Richard III to be friends of traitors and betrayed by friends and Queen Elizabeth to later wish for Margaret's help to curse Richard III. Margaret spares
Buckingham telling him he hasn't wronged her, but he insults her so she curses him too.
In the Tower of London, Clarence relates a dream to his keeper, in which Clarence drowns and sees his father-in-law, Warwick, cursing Clarence for deserting him at Tewksbury. Two executioners, paid by Richard III, then murder Clarence by drowning him in a wine barrel. At the London palace, sick Edward IV makes Queen Elizabeth, Hastings, Dorset, Buckingham, and Rivers to bury their differences and make up. Richard III enters and makes peace too, then informs them all of Clarence's death, after-which Edward IV repents the death. Cicely Neville (Duchess of York, 3rd Duke of York's widow) tells Clarence's children, Edward and Margaret Plantagenet, that their father is dead. Edward IV dies and Queen Elizabeth laments. The children criticize Elizabeth for not mourning Clarence's death.
Queen Elizabeth learns that her sons, Grey and Dorset, have been moved to Pomfret Castle by Richard III and Buckingham. Queen Elizabeth, her son Richard Duke of York and the Duchess of York flee to sanctuary. Prince Edward V arrives in London and sends Hastings to bring his brother Richard, Duke of York out of hiding and to him. Richard III sends Richard Duke of York and his brother Edward V to the Tower of London to "sleep", though he, Buckingham, and Catesby plan to kill the boys and crown Richard III king. In return, Richard III promises Buckingham land. Catesby tries to convince Hastings to side with Richard III, but he refuses. All learn that Rivers, Vaughn, and Grey have been executed at Pomfret castle. At the Tower, Richard III accuses Hastings of treason and has him beheaded.
Richard III tells Buckingham to start rumors that Edward IV's children are bastards, and furthermore, that Edward IV himself was a bastard. Also, Richard devises a plan to get rid of Clarence's children. The mayor of London comes to Richard III and offers him the throne, which Richard, reluctantly accepts. The Grandma Duchess of York, Queen Elizabeth, and Anne mourn because Richard III imprisoned the princes in the Tower of London. Queen Elizabeth tells her son Dorset to leave England to see Richmond (Henry VII), after Stanley brings news that Richard III plans to crown Anne Neville queen, fulfilling Anne's own curse that Richard III's future wife be cursed and miserable.
At court, King Richard III asks Buckingham to murder Prince Edward and his brother, but Buckingham refuses. Richard III plans to get Clarence's daughter married off to a poor man to get rid of her. Richard also plans to kill his own wife Anne Neville and marry his own niece Elizabeth, Edward IV's daughter. Richard III pays Tyrrel to kill the princes. Richard III remembers a prophesy that Richmond (future Henry VII) would be king someday. Anne and the princes are killed, Elizabeth is married off, Clarence's son Edward is killed, and Richard III tries to court his niece Elizabeth so that she may leave Richmond. However, Ely joins Richmond and Buckingham to raise an army against Richard III. Old Queen Margaret (Henry VI's wife) meets the Duchess of York and Queen Elizabeth and tells them to curse Richard III, and they do. Richard III tells Queen Elizabeth that he wants to marry her daughter Elizabeth. Battle continues, Richmond attacks England and Buckingham losing on the losing end. Stanley would help Richmond, but Richard III keeps Stanley's son as insurance so as to ensure that Stanley doesn’t betray him. Richard III orders Buckingham to be executed. Richmond, Oxford, Blunt, Herbert, and William Brandon are together against Richard III, Norfolk, Radcliffe, Surrey, Catesby, and Northumberland.
The ghosts of all of Richard III's victims come to him in a dream to haunt and torture him. They all say, "Despair and die" to Richard III, causing him to go insane. The same ghosts also visit Richmond and wish him luck. The two armies meet in battle on Bosworth Field, both generals giving orations to their armies before battle. On the battlefield, Richmond kills Richard III and Stanley crowns Richmond as Henry VII. Henry VII, a Lancaster, marries Edward IV's daughter Elizabeth, a York, ending the War of the Roses by uniting the houses of York and Lancaster.