ABIQUIU  -  An entire town filled with nuclear labo­ratories, built from scratch in the remote mountains of New Mexico, with every single person involved sworn to secrecy? It is not just the plot of “Oppenheimer,” but also the story of how Christopher Nolan’s Oscar-nominated movie about the invention of the atomic bomb was made. “This is the most I’ve ever spoken about it,” said David Manzanares, field producer for Ghost Ranch, as he took AFP on a recent tour of the location for the movie’s Los Alamos scenes. “It definitely took on the air of secrecy,” he recalled. A few miles from the nearest paved road, through gates marked “RESTRICTED AREA,” many of the wooden homes, of­fices, security checkpoints and even a chapel built for the film remain stand­ing. The buildings line a dusty street that is bookended by stunning purple-hued mountains. The real Los Alamos, an hour’s drive away -- is now a mod­ern town that remains home to a giant, top-secret government lab charged with safeguarding the US nuclear stockpile. Its historic buildings were used for sev­eral interior scenes. But Nolan selected this far corner of the southwestern US state to double as the town for exterior scenes, constructing a 1940s-era replica of its main street. The British filmmak­er famously insists on using authentic, practical sets to inspire his actors. The movie’s atomic bomb test was shot with minimal computer effects, and real Los Alamos scientists were hired as extras. This meant the replica of the town had to be built at full-scale, offering Nolan the possibility of filming from every angle at a moment’s notice. But until a month after the film premiered last July, Man­zanares and his Ghost Ranch team were not even allowed to acknowledge that the movie had been shot there. “There was no conversation, there was no post­ing” allowed, he said. “That’s just the way business is conducted on a Christopher Nolan shoot.” In mid-October 2021, Man­zanares was contacted by a friend who works as a location manager for movies, asking if he knew of any pristine sites with wide, sweeping vistas. The friend could not say what the project was, but shared that it was set in 1940s New Mex­ico -- enough for Manzanares to hazard a guess, given the buzz already surround­ing Nolan’s next big film. Ghost Ranch fit the bill, and the following month, Nolan himself came to check it out.