Harold is a character appearing in Professor Layton and the Unwound Future. He works in the Gilded 7 Casino. At first, Harold is a doorman, and only lets people who have membership cards in the casino. Harold, after solving his puzzle, lets Professor Layton and Luke in just this once. After the shootout in the Casino, Harold gets demoted because he let Layton and Luke in. The Casino reopens around Chapter 12. After that he gives Layton and Luke a puzzle so they forget about the whole mess.
Harold gives Layton and Luke a couple of puzzles during the course of the game. The first puzzle he gives them is "A Game of Cards". Later on, when the Casino reopens he gives Layton and Luke the puzzle "Quriky Clockwork".