The veteran actor has played the role of headmaster Albus Dumbledore in the hit films since the third instalment, Harry Potter and the Prisoner of Azkaban.
But Gambon refuses to read the J.K. Rowling novels the franchise is based on - as he's worried it would spoil the joy of acting out the scenes.
He says, "There's no point reading the books because you're playing with the screenwriter's words. Besides, you'd get upset about all the scenes the script is missing from the book, wouldn't you?".