Even by the standards of a Robertson Davies character, Magnus Eisengrim has gone through a remarkable series of transformations by the time he recounts his life history in World of Wonders. He was born Paul Dempster in Deptford, and became Cass Fletcher when, at the age of ten, he was kidnapped by an abusive magician from the World of Wonders circus. He later worked as a magician on his own account, this time under the name of Faustus LeGrande, in France, before becoming a stunt double for Sir John Treize, a famous English actor.
Paul Dempster did not have an easy start in life. He was born prematurely to a mother who was rapidly overcome by insanity. At the age of ten, he was raped and kidnapped by a man who then tortured him physically and psychologically for years. However, he showed his resilience by using his position at the circus to learn to be a conjurer. After the death of his abuser, Willard the Wizard, Dempster used the skills he had learned to create a new life for himself, as well as a new identity. At first he was merely imitative, copying Sir John Treize when he had an opportunity to observe him at close quarters. By the time he becomes Magnus Eisengrim, however, he has composed himself into the successful magician and film actor he wants to be, influenced by his past, but directed by his own will.