The street does most of the work. Iain Macmillan's photograph of the Beatles crossing Abbey Road on 8 August 1969 is remembered as four men on a zebra crossing, but the real compositional engine is that receding north London road — tree-lined, sun-bleached, vanishing into a blue sky that looks painted rather than real. Without it, you have four famous men walking. With it, you have a portal. This was not a photograph taken by chance. McCartney sketched the concept himself — stick figures on the crossing, viewed from above — and brought it to Macmillan. On the day, they got a police officer to stop traffic. Macmillan stood on a stepladder. Six frames were shot. The whole session took about ten minutes. The apparent casualness is the design. McCartney had been collecting paintings by René Magritte since 1966, and the Magritte fingerprint is all over this image: a scene that is entirely ordinary and entirely wrong at the same time. Hyper-real perspective, deadpan foreground, the nagging sensation that the image is asking you something it won't answer. The 'Paul is dead' conspiracy — Starr as undertaker, Harrison as gravedigger, McCartney barefoot as the corpse — is a daft theory, but it is also proof that the image successfully demands interpretation. It was designed to. What the photograph actually captures is the tension the Beatles had always exploited: four distinct individuals who functioned, at their peak, as a single organism. Lennon leads but his face is half-turned away — the only Beatle you can't fully read. He told the band he was leaving that September. McCartney, the picture's author, is barefoot: he doesn't want to go anywhere. The photograph is a freeze-frame of a band walking in the same direction for the last time, composed by the one member most desperate for them not to. The image has proven almost infinitely reproducible — Red Hot Chili Peppers, Kanye West, Franciscan friars, Booker T and the MGs, and now Sam Mendes, who recreated it for his four Beatles biopics. Each recreation confirms what makes the original work: it is specific enough to be iconic (zebra crossing, north London, summer light) and open enough to accept any allegory you bring to it. The 'Paul is dead' reading, the 'band breaking up' reading, the pure-formalism reading — all of them fit because McCartney built a container, not a message. The British-ness of it matters more than it might seem. Zebra crossings are a specifically British institution, and that ordinariness is load-bearing. This could only be London. The image works because it takes the most famous band in the world and places them in the most mundane civic infrastructure imaginable — and the friction between those two facts is where all the meaning lives.