"During the filming of The Wizard of Oz, the director, Victor Fleming, was looking for a coat for Professor Marvel. He wanted something that looked as if it had been beautiful once but was now falling apart, and he found just the thing in a secondhand shop. When he got it back to the costume department they found a name tag. The coat had belonged to L Frank Baum, author of the original book. No matter how fanciful what we write is, we always bury something of ourselves in the foundations. And sometimes that something comes back - like Frank Baum's coat - to haunt or bless us."