Revealing mistake: The spiders advancing on Harry and Ron during the visit to Aragog are not the same in appearance. In some of the closeups a few have elongated bodies, while others are medium-sized. And many of them look quite aged, like Aragog himself.
Harry Potter and the Chamber of Secrets (2002)
41 revealing mistakes
Directed by: Chris Columbus
Starring: Maggie Smith, Alan Rickman, Kenneth Branagh, Richard Harris, Daniel Radcliffe, Jason Isaacs, Emma Watson, Robbie Coltrane, Tom Felton, Rupert Grint, Richard Griffiths
Genres: Adventure, Family, Fantasy, Harry Potter, Mystery
Visible crew/equipment: In the dueling scene, when Snape pulls Malfoy back onto his feet, a cameraman is visible kneeling down on the far left of the screen (Widescreen version only). (01:07:46 - 01:20:00)
Harry Potter: It's all right Ginny, It's over. It's just a memory.
Trivia: The first scenes in the movie are some of the last scenes filmed. Viewers kind of tell by the way the actors' voices and looks changed. For example, Matthew Lewis (who played Neville Longbottom) said that he had to stuff cotton balls in his cheeks in the "Mandrakes in the Greenhouse" scene, since he had lost so much weight since the beginning of filming.
Question: Is this true that line "I didn't know you could read" was improvised by Tom Felton, who forgot his original line?
Answer: Yes in the same way Daniel Radcliffe improvised his line about always being around when talking to Lucius at the end.
Actually, Jason Isaacs said that, and he and Daniel didn't forget their lines but did it intentionally.
Answer: Yes. It's a common occurrence in a lot of movies for actors to forget their original lines so they improvise something to help move the scene along and not break character. Tom did this because he forgot what his original line was.