It’s no secret by now that Damien Chazelle’s La La Land featured some unbelievably ridiculous camerawork. Now that the film has been nominated for Best Picture and Best Cinematography, as well as Best Director, Best Editing, and Best Production Design, the film’s campaign is making sure the Academy voters know exactly how much it deserves to win in the technical categories.

The opening number, “Another Day of Sun,” is, for many, the best part of the entire movie. It’s a single take, fantastically intricate dance number featuring a ton of suberbly talented triple threats (who we, unfortunately, never see again). In a jab at the terrible traffic Los Angeles suffers daily, the actors dance on top of and around their gridlocked cars, singing about moving to the city riding on ambition and the hope of becoming a big star, while also mentioning that the weather in LA is consistently bright and sunny. In this new behind-the-scened video, Chazelle reveals how he rehearsed the number with his cast before heading out on the road, using a vacant parking lot and about twenty cars to get the routine just right.

In the description for the video, USA Today mentions that Chazelle mapped out the entire dance number on his iPhone. This video “Became sort of our bible,” he and choreographer Mandy Moore (no, the other one) told USA Today. The actual dress rehearsal on the highway ended up being a disaster, because the choreography looked weird, and the crane couldn’t move like an iPhone could, so they had to go back and work out some of the kinks. Luckily, a few weeks later when they shot the actual scene with Ryan Gosling and Emma Stone among them, it ended up working out.

“We went back to the location, a little chastened, a little humbled and a little nervous,” Chazelle said. “And then we shot the real thing, which you see in the movie.”

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