Picture the scene. It's an ordinary Tuesday morning and our hero, Dan Brown, has a new book out He could taste the familiar tang of museum air - an arid, deionized essence that carried a faint hint of carbon - the product of industrial, coal-filter dehumidifiers that ran around the clock to counteract the corrosive carbon dioxide exhaled by visitors. Someone did his air-related research! No, seriously. It is easy to be rude about Brown's writing - especially, you might say, when he writes like this. But literary snobbery looks a bit silly against the cold, hard (arid, deionized ...) fact of 200 million novels sold worldwide. On Tuesday, Brown publishes Inferno, the fourth instalment in the treasure hunt series which began in 2003 with The Da Vinci Code. This time, Langdon will be caught up in a mystery inspired by Dante's masterpiece - Abandon hope, all ye who enter here! - and if it is anything like his last novel, The Lost Symbol, it will sell a million copies before the sun sets on Tuesday night. For months now, fans have been feverishly poring over clues disguised in the cover design. This week, translators jumped on the hype juggernaut with stories of their time in Dan's Inferno - locked in a bunker since February 2012 with scanty time off to eat and sleep as they prepare the manuscript for simultaneous publication worldwide. Next week, the burden passes to the world's literary editors who will speed-read all 480 pages and deliver their instant verdict. Brown is a phenomenon, but will Langdon fever take hold this time around? When The Da Vinci Code was published, Harry Potter aside, literary sensations were still relatively rare. These days, thanks to the one-click fix of the Kindle, every month throws up a 50 Shades of Grey or a Gone Girl. And this, surely, is a good thing. The critics might hate these blockbusters, but I still get a thrill when the publication of a new book becomes a global event. The market of potential readers who may pick another thriller off the shelf with Inferno, or look for other things to devour in the four years it takes Brown to write his fifth instalment, is huge. And the profits he will pour back into the ailing industry are not to be sneered at. Even if he makes it all too easy to sneer at his prose. Here comes wedding season. And, I'm afraid, brides and grooms-to-be, the bar has been raised. This time by Keira Knightley who married James Righton in a paparazzi-perfect ceremony last weekend. According to Sir Paul Coleridge, a High Court Judge who established the Marriage Foundation to encourage people to wed, the actress and indie star have set a fine example with their "low-key" celebration. Knightley's nuptials - which featured a recycled dress, guests in flip-flops and a Renault Clio instead of a Rolls-Royce - could set a new trend for no-frills ceremonies, he said. If people thought that they could not get married unless they had a glittering celebrity-style wedding ... that's tragic. He is quite right. And Knightley's wedding looked as happy and charming an occasion as you could wish for. But low key? If you're a High Court judge, perhaps. The recycled dress was couture Chanel; the flip-flop wearing guests in Provence included Sienna Miller and Karl Lagerfeld and the Clio drove them all to party in a chateau. It takes an awful lot of effort, and probably cash, to look effortless on one's wedding day. Coleridge has fanned the flames of celebrity envy with his comments. Low-Key will be the next big wedding trend. Expect Ray Ban-wearing happy couples and bridal flip-flop ranges to follow.