You can’t fault the cover, which is really delightful: a red damask wall, hung with works by Watteau which the paper jacket reveals in enticing details through pierced and framed oblongs, beneath endorsements by Barbara Trapido and Elizabeth Gilbert. Inside is a story about another Watteau, a rediscovered masterpiece, which is based on the real-life re-emergence in 2008, after 200 years, of his painting La surprise. This may lead you to expect another Headlong, Michael Frayn’s terrific and erudite hoot of a book about the discovery of a long-lost Brueghel, or perhaps something like Giles Waterfield’s hilariously spiky satire involving a suspect Gainsborough, The Hound in the Left-Hand Corner.However, as we are always being told, it is fatal to judge a book by its cover.