5/8
Jerry Bruckheimer/Walt Disney/Kobal/Shutterstock
9. Signing on as Ben's mother in National Treasure: Book of Secrets, Helen Mirren was forced to turn down an invitation to visit Queen Elizabeth II, sent in response to her portrayal of her in the 2006 film The Queen, because she was busy filming in South Dakota at the time.
10. The area in the Library of Congress where the titular Book of Secrets is found by Cage's character doesn't house any book shelves. They were constructed in a previously empty balcony of the Library's Main Reading Room and dismantled once filming was over.