The importance of the number 7 throughout the saga
For starters, there are seven volumes in J.K. Rowling's story. Then, central to the story there are seven Horcruxes, Harry is even the seventh. In the second instalment, Harry Potter and the Chamber of Secrets, the entrance to the chamber is adorned with a seven-headed snake! In The Deathly Hallows, six characters drink polyjuice potion in order to look like Harry and cover their tracks from Voldemort and his army. So we even get seven Harry Potters on screen! We could go on but now the goal is to reread the saga and find all the occurrences of this important number.
Gilderoy Lockhart is bald
It’s hard to imagine this character without hair. He is so narcissistic and vain and the image he puts forward is one of his priorities in life. However, when Ron and Harry go to Gilderoy Lockhart's office, we can see a strange wig lying on the table. It looks exactly like the professor's hairstyle…
Dumbledore’s hidden room
Where does Albus Dumbledore live? His home is never mentioned in the movies, but the headmaster of Hogwarts has a room behind his desk. No scene was ever shot in this room but it does exist. An English journalist reported this fact after having had the chance to visit the movie set.
The return of the chocolate frog
In the first film, Harry meets Ron on the Hogwarts Express. They take the opportunity to gorge themselves on sweets thanks to Harry's money, who then stumbles upon a special treat. It's a chocolate frog that comes to life when its box is opened, which then escapes out the moving train’s window. In the final scene of the last movie, Harry’s and Hermione and Ron’s children get on the train for their turn at Hogwarts. The frog from the beginning then lands on the window, thus closing the loop of the big adventure.