At 3.30am on the night of 23 April 1993, at a secret location in France, in pitch-blackness a man dug a hole. In it, Max Valentin, hid a small bronze owl sculpture, instigating what would become one of the world’s longest treasure hunts. The location could be found by solving 11 riddles published in a book, On the Trail of the Golden Owl. Whoever unearthed the owl would win an identical sculpture, made of gold, silver, rubies and diamonds, worth about €150,000. But Valentin died 16 years later to the day, with the owl still undiscovered. It’s still out there now. The Blindest Man is about obsession and obsessives. Emily Graham is an acclaimed British photographer.