For a three-act plot analysis, put on your screenwriter’s hat. Moviemakers know the formula well: at the end of Act One, the main character is drawn in completely to a conflict. During Act Two, she is farthest away from her goals. At the end of Act Three, the story is resolved.
Act I
York has won a crucial battle against Henry, and he tries to take the crown. After an agreement is struck up and destroyed, Margaret storms York's castle with her troops. Both sides fight to the death, and Margaret captures and beheads York. Game on, sister.
Act II
Edward takes over for York with the help of his brothers and Warwick. They want France as an ally, so they send Warwick to ask the French king's permission for Edward to marry Lady Bona. He does, and the wedding is all set, but in the meantime, Edward rushes off and marries Lady Grey instead. Furious, Warwick joins up with Margaret—and France backs them. George betrays his bro Edward and joins up with Warwick and Margaret, too. Good luck, Edward.
Act III
The war is on, and Warwick dies in the heat of battle. Edward eventually wins and kills or captures the rest of his enemies. Margaret is shattered when her son is killed right in front of her, and she wants to die herself. But Edward doesn't do her any favors. He's happy to be king and a new dad, and he celebrates with his fam. Richard, however, has a plan of his own: he wants to take down the new king and steal the crown for himself.