Harry Potter and the Prisoner of Azkaban is a 2004 fantasy film directed by Alfonso Cuarón and distributed by Warner Bros. Pictures. It is based on the novel of the same name by J. K. Rowling. The film, which is the third instalment in the Harry Potter film series, was written by Steve Kloves and produced by Chris Columbus (director of the first two instalments), David Heyman, and Mark Radcliffe. The story follows Harry Potter's third year at Hogwarts as he is informed that a prisoner named Sirius Black has escaped from Azkaban intending to kill him. Wikipedia
Ron: Neville, you're supposed to stroke it!