The dust cover features one of the best-known caricatures of Richard Wagner, his enormous head in this version opened like a boiled egg, with a photograph of Simon Callow either emerging from his skull or sinking into it. The idea is that rather than just writing another book on this over-biographised figure, Callow will let us know what it was like actually to have been him, something he also tried in his one-man show at the Linbury Theatre, Inside Wagner’s Head.