The Library - S1-E3
Revealing mistake: In the extra 'Library' scene, the book that Bean is given already has the loose pages before he has been at them with the knife. (At one point the pages get pushed forward a little bit, meaning that they're not fastened into the book.)
The Library - S1-E3
Revealing mistake: Just before Mr Bean rips a page out of his book, there is already a tear in it just before he actually tears it, which is not visible in any of the preceding shots.
The Library - S1-E3
Revealing mistake: When Mr Bean's book falls apart, he tries putting the book back together, and he holds one page up to the camera and it has a slight reflection as if it is glossy paper. As far as I know old books like the one Mr Bean had don't have pages like that. It's an obviously fake book.
Chosen answer: I'm guessing it is because he bought a new car. At the end of the first Bean, he crashed the mini. You hear the crash and see his wheel bouncing down the road. Safe to assume it was a write-off.
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