Series 
Series 
Deliberate "mistake": While it is established that Angel doesn't age, it's obvious across both Buffy and Angel that David Boreanaz gets older. More unavoidable than deliberate, but still worth noting. Submitted by Cubs Fan
Buffy The Vampire Slayer (1997) - 1 mistake in whole show
Directed by Joss Whedon, starring Alyson Hannigan, Amber Benson, Anthony Head, Charisma Carpenter, David Boreanaz, Emma Caulfield, James Marsters, Marc Blucas, Michelle Trachtenberg, Nicholas Brendon, Sarah Michelle Gellar, Seth Green
Across whole show
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