In the first movie, when Evie, Jonathan and Rick are getting into the car after finding out where the Book of Amunra is: The mummy is looking down at them from the room window. If you look behind the mummy, there is his own shadow. This is obviously impossible because the light from the lamp in the room that he's in is coming from behind him. Therefore, his shadow would be on the window cill and on the ground where he is looking!