<Li> Maggie Smith as Minerva McGonagall, the Deputy Headmistress, head of Gryffindor and transfiguration teacher at Hogwarts. Smith was Rowling's personal choice for the part . </Li> <Li> Julie Walters as Molly Weasley, Ron's caring mother . She shows Harry how to get to Platform ​ 9 ⁄ . Before Walters was cast, American actress Rosie O'Donnell held talks with Columbus about playing Mrs. Weasley . </Li> <P> Rik Mayall was cast in the role of Peeves, a poltergeist who likes to prank students in the novel . Mayall had to shout his lines off camera during takes, but the scene ended up being cut from the film . David Bradley portrays Argus Filch, the loathed caretaker of Hogwarts . Tom Felton portrays Draco Malfoy, the trio's enemy . Zoë Wanamaker portrays Madam Hooch, the flying teacher of Hogwarts . Sean Biggerstaff portrays Oliver Wood, captain of the Gryffindor Quidditch team . James and Oliver Phelps appear as Fred and George Weasley, Ron's older twin brothers . Chris Rankin portrays Percy Weasley, Ron's older Prefect brother . Bonnie Wright portrays Ron's younger sister, Ginny Weasley . Harry Melling plays Dudley Dursley, Harry's Muggle cousin . Matthew Lewis, Devon Murray and Alfred Enoch portray Neville Longbottom, Seamus Finnigan and Dean Thomas, respectively . </P> <P> In 1997, producer David Heyman searched for a children's book that could be adapted into a well - received film . He had planned to produce Diana Wynne Jones' novel The Ogre Downstairs, but his plans fell through . His staff at Heyday Films then suggested Harry Potter and the Philosopher's Stone, which his assistant believed was "a cool idea ." Heyman pitched the idea to Warner Bros. and in 1999, Rowling sold the company the rights to the first four Harry Potter books for a reported £ 1 million (US $1,982,900). A demand Rowling made was that the principal cast be kept strictly British, nonetheless allowing for the inclusion of Irish actors such as Richard Harris as Dumbledore, and for casting of French and Eastern European actors in Harry Potter and the Goblet of Fire where characters from the book are specified as such . Rowling was hesitant to sell the rights because she "didn't want to give them control over the rest of the story" by selling the rights to the characters, which would have enabled Warner Bros. to make non-author - written sequels . </P>

Why is the movie called harry potter and the philosopher's stone