Illustration by Kristian Hammerstad In the final volume of Proust’s great novel, In Search of Lost Time , the narrator attends a devastating soirée at which he scarcely recognises anyone. The partygoers, whom he first met when he entered society 20 years before, have been degraded by time. That’s also how long it has taken for this The Devil Wears Prada sequel to arrive. It’s not because there was no demand. The teaser trailer for this continuation was viewed 181.5 million times in its first 24 hours, the full trailer 222 million times. But, as the director David Frankel endearingly explained to the audience at the London premiere “for almost two decades we just didn’t have a good enough idea” for a second movie. That idea, when it came, was proposed by the original’s scriptwriter, Aline Brosh McKenna.…