Harry Potter fans have spotted a 'hidden theme' in the opening credits of every film as the Warner Bros. logo gets 'darker' in each movie, reflecting the growing darkness of the storyline.
Settling down to watch the entire Harry Potter series is a favourite winter pastime for many, which tells the story of a young wizard and his friends as they solve mysteries and repeatedly defeat the evil Lord Voldemort.
As each magical school year passes, the story becomes more scary and complicated, ending in a fierce fight between good and bad.This dramatic change in mood and shift towards more grown-up themes is also seen in all of the opening credit sequences, and the 'hidden theme' is really clear once you spot it.
Some viewers have noticed that the famous Warner Bros. logo gets darker with each film, showing the growing darkness in the wizarding world as Voldermort gets his evil powers back.
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