"Something wicked this way comes."
Harry Potter and the Prisoner of Azkaban - Easter Eggs & Hidden Details
Easter Eggs
A portrait of the director's wife and daughter can be seen in the background.
In the scene where students are walking up the Grand Staircase after Sirius Black's first break-in attempt, a portrait of a woman holding a baby is visible. This is a cameo of Alfonso Cuarón's then-wife and their daughter, adding a personal touch from the director to the magical world.
The 'Mexican Hat Dance' is whistled by Dumbledore.
Towards the end of the film, as the students are leaving, Dumbledore can be heard whistling "Jarabe Tapatío," more commonly known as the "Mexican Hat Dance." This is a playful nod to director Alfonso Cuarón's Mexican heritage.
Ian Brown, lead singer of The Stone Roses, makes a cameo.
In the Leaky Cauldron, when Harry is reading 'A Brief History of Time', the man sitting at the table magically stirring his drink is Ian Brown. Alfonso Cuarón is a fan of the band and included him in the scene.