On a Wednesday morning in Los Angeles, George Lucas — the man who conjured galaxies far, far away — confessed that a building had nearly defeated him. "I'm used to doing the impossible," he told the gathered press, "but this one almost broke my will." The institution in question, the Lucas Museum of Narrative Art, has been fifty years in the making if you count from the moment Lucas began quietly acquiring paintings in the 1970s, and more than eight years in construction after earlier attempts to plant it in San Francisco and Chicago both collapsed under the weight of civic opposition. It opens to the public on 22 September, rising like a grounded spacecraft above the University of Southern California — the very campus where its founder once learned his craft.

Inside, 100,000 square feet of gallery space hold a collection that refuses to be easily categorised. Works by the Mexican muralist Diego Rivera hang within sight of Norman Rockwell's sentimental Americana; Banksy's subversive stencils share territory with the original costume of the Cowardly Lion from The Wizard of Oz, while drawings of Asterix and Garfield assert that comics are as deserving of a museum wall as any oil on canvas. What binds these seemingly unrelated objects, as co-founder Mellody Hobson explained on Wednesday, is their shared function: each one tells a story, frequently within a single, arrested frame. The museum's architect, Ma Yansong, has said he drew his inspiration not from science fiction but from tree canopies and drifting clouds, though the building's sleek, saucer-like silhouette makes that claim feel charmingly modest.

A central plaza between the museum's two wings contains an oculus — a circular opening cut into the structure — through which visitors are invited to contemplate, in Yansong's own words, "the sky and the universe." Senior curator Ryan Linkof framed the entire enterprise in more earthly terms, arguing that narrative art is "the art that surrounds us," woven into newspaper photographs, book covers, street murals, and cinema screens so thoroughly that most people absorb it without a second thought.