The best music documentaries of 2021, from Britney’s quest for freedom to the Beatles’ final days to Billie Eilish’s journey to fame

• Peter Jackson’s The Beatles: Get Back traces the band’s final days, while Billie Eilish’s rise to fame is the subject of The World’s a Little Blurry
• Controlling Britney Spears offers a blow-by-blow account of the court proceedings as the singer sought to escape a conservatorship overseen by her father