He is first seen riding in a carriage with his uncle Edgar and Edgar's pet snake, Heston. He is not excited at all about becoming king.
When he is chased by obsessed girls, he and Ella meet for the first time. Her attitude towards him attracts him to her, as she is the first person he's met who didn't swoon at the sight of him. After he saves her from being driven over by a carriage, Hattie comes and orders Ella to go. He is immediately appalled by her.
Prince Charmont rescues Ella and Slannen from being eaten by ogres. He goes along with her to the Giants' wedding. The next day, he invites Ella to his castle, where she meets Sir Edgar. He invites Ella to the coronation ball but it was taken by Ella's stepsisters. Later, Ella and her new friends stopped the ceremony by her saying "Drop that crown!" She explained to the prince that his uncle killed his dad, and Heston tried to bite him. However, Charmont is rescued by Ella, and Heston is trampled by his fan club, and it shows Ella was telling the truth, and the prince couldn't believe that his uncle would kill his own brother and his father, but after his uncle collapsed from the poison (he survived), he asked Ella to be his princess, and this time, she happily agreed.
Differences from the source material
His parents are not dead.
In the film, he says he doesn't have any siblings, but in the book, he mentions he has a younger sister.
He doesn't have a known uncle.
He heard stories about Ella from one of the royal cooks, who associated with Mandy.
He meets Ella at her mother's funeral.
He doesn't have to rescue Ella from the ogres, because she "tamed" them by speaking Ogrese in their oily way, and thus befriending them.
He leaves for Ayortha for a year, and writes letters to Ella.
He proposes to Ella in one of his letters. Ella declines by lying to him that she is married to an elderly person along with writing a letter in the name of Hattie, saying that she (Ella) is a minx and not to bother with them.
Three balls are given in his honor. At the last ball, Ella's identity is revealed.