Perhaps his most significant role in 2004, however, was Albus Dumbledore, Hogwarts' headmaster in the third installment of J. K. Rowling's franchise, "Harry Potter and the Prisoner of Azkaban", taking over from fellow Irish actor Richard Harris, who had died of Hodgkins disease. (Harris had also played Maigret on television four years before Gambon took that role.) Gambon reprised the role of Albus Dumbledore in "Harry Potter and the Goblet of Fire", which was released in November 2005 in the UK and U.S. He returned to the role again in the fifth movie, "Harry Potter and the Order of the Phoenix", which was released in 2007. He will once again return to portray Dumbledore in movie the sixth "Harry Potter and the Half-Blood Prince". Gambon admits not having read the "Harry Potter" novels and says that this is because he does not want to be upset by an extremely large change or death in the books. Similarly, he has also stated in an interview that, when playing Dumbledore, "I don't have to play anyone really. I just stick on a beard and play me, so it's no great feat. I never ease into a role – every part I play is just a variant of my own personality. I’m not really a character actor at all..."