His latest novel "The Secret Books" makes it clear from the outset: stories are slippery things, subjective takes that have often gone on to constitute the very foundations of human civilisations. Marcel Theroux has carried out a literary investigation into a spiritual mystery dating back two millennia and, in doing so, takes the reader on a trip through 19th century France and Russia. Theroux tells us how he was compelled to look into the story of eccentric, real-life protagonist Nicolas Notovitch and about his own complex relationship with fiction.