Even though this year's Coachella festival has been pushed back to October due to the COVID-19 pandemic, a documentary about the history of the beloved annual ritual will still come out on the day the fest was to kick off, April 10.Coachella: 20 Years in the Desert opens with voiceover from Billie Eilish saying, "Everybody knows what Coachella is," over footage of her headlining set last year. "Even if you don't care about music you know." The three-and-a-half minute teaser then shuttles between bits of Jimmy Kimmel, Family Guy and Pres.