Focusing Tiny Sunbeams

A good month before Harry gets back from Hogwarts, Dudley is bored, and stuck for things to do. His friends are still in their term, and boxing practice can only take up so many hours in a day... So when he finds an opportunity to pick up some big money, he wastes no times landing himself in a game of time travel, psychic powers, and a possible death with an unmarked grave.