1. The producers tried to give Harry Potter green eyes and Hermione buck teeth like in the books, but failed. Sadly, Daniel had a terrible allergic reaction to his green contact lenses and had to stop wearing them, while Emma Watson couldn’t speak clearly wearing her false buck teeth.
2. The Duke Humfrey’s Library made a huge exception for filming The Restricted Section scene. Even though the historic library usually strictly forbids bringing flames into the library for any reason, they made an exception for Harry Potter. It was the first exception in hundreds of years.
3. Rupert Grint has an actual severe case of arachnophobia. So he didn’t have to do much acting in the scene where he and Harry meet Aragog.
4. Hermione was meant to hug Harry AND Ron at the end of the movie when she runs into the Great Hall. Because Emma Watson was too embarrassed to hug the boys in the scene, Christopher Columbus changed it so that she would hug Harry and then begin to hug Ron but get too embarrassed and shake his hand. The change actually worked well to build up their love/hate relationship that continued throughout the books. We all know how that ended!
5. The case of the three Dumbledores. The role of Dumbledore was recast because Richard Harris (the original Dumbledore) sadly passed away shortly after Chamber of Secrets was released. Many people mistakenly believe Ian McKellan took over the role of Dubmledore, but it was actually Michael Gambon who took on the role. The confusion probably stems from Ian’s role as the legendary Gandalf in “Lord of the Rings,” who looks very similar to Dumbledore.
6. Why Harry was only shown dancing from the waist up in the Yule Ball scene might surprise you. While the rest of the cast got three weeks of dancing practice, Daniel was only able to get in four days because he had a much heavier filming schedule. For this reason, they mainly used shots of Harry dancing from the waist up to avoid showing his stumbling feet.
7. The character Nigel, who first appears in GoF and then in OotP, does not appear in ‘Harry Potter’ books at all. It is believed that he was introduced to act as a substitute for Colin Creevey and his brother Dennis because of his short stature, and his idolizing of Harry.
8. The Black family tree portrait was super authentic. J.K. Rowling actually provided over 70 names for the Black family tree tapestry, along with details of relations between every member.
9. The actor who played Young Tom Riddle is related to the actor who played Voldemort. Hero Fiennes-Tiffin is actually Ralph Fiennes’ nephew.
10. The script prompted J.K. Rowling to first reveal Dumbledore is gay in ‘Harry Potter’. The original script included a line where Dumbledore talks about a crush he once had on a girl, which led Rowling to clarify that Dumbledore was gay and only ever had a crush on the great wizard Grindelwald. She later made this public information while promoting the final book in the series.
11. Filming the “Seven Harrys” scene was insanely complex. Daniel Radcliffe counted over 90 takes just for that single shot.
12. Bill Weasley and Mad Eye Moody have a familiar connection. Domhnall Gleeson portrays Bill Weasley and is the son of Brendan Gleeson, who plays Mad Eye Moody. Can you spot the resemblance?
13. Daniel Radcliffe went through 160 pairs of prop glasses by the end of filming the series.Which is oddly fitting since he probs would have gone through that many in the books too had it not been for the Reparo charm.