"Boggarts are shape shifters" says Hermione Granger in the 2004 much acclaimed Harry Potter and the Prisoner of Azkaban movie. "They take the shape of whatever a person fears the most. That's what makes them so terrifying." As Professor Remus Lupin teaches them the defense against Boggarts spell; "Riddikulus!" he adds "..what really finishes a boggart is laughter. You need to force it to assume a...