Harry Potter and the Prisoner of Azkaban

After the death of Richard Harris, many actors were considered for the vacant role of Albus Dumbledore. Christopher Lee was in the frame for a while, and there was a rumor (reported in many newspapers) that Ian McKellen was also considered. The Harris family wanted Richard's longtime friend and peer Peter O'Toole for the role but there were studio concerns over insuring O'Toole for the remaining five films. Richard Attenborough also lobbied for the role but was ultimately turned down. The role eventually went to Michael Gambon.