A change in character...

      So in the beginning of Miss Peregrine's Home for Peculiar Children, the grandfather of the main character is presented as somewhat psychotic. He died in a mysterious way, thought to be the fault of his own insanity. However, as the book progresses, you see that maybe he wasn't so crazy after all. He left behind a letter for his grandson, telling him about an small island that hold the key to his unusual past. As he visits the island and learns more of his grandfather, you find out who he really was. It's a great change in character, revealing that he was very intelligent after all.