Duke is a character appearing in Professor Layton and the Diabolical Box. Both his appearance and his attitude seem to be rather aloof. He is one of the people to whom Layton and Luke must talk in order to gather all of the pieces of the missing photo scraps. Duke is seen, throughout Layton and Luke's time in Folsense, around the Museum's single entrance.
Duke gives Layton and Luke a single puzzle during the course of the game. The only puzzle that Duke gives Layton and Luke is the puzzle "Turn On the Light". This puzzle must be solved in order to obtain a photo scrap.
Though it can seem like Duke talks down to people, it's actually just the unfortunate way he holds his face that makes him seem that way. His softer side comes out when he's with his little brother, Niles.