How many artists does it take to properly cover a Beach Boys classic?
Let's say more than two dozen famous musicians, plus Brian Wilson from the Beach Boys' original lineup, the Tees Valley Youth Choir and the BBC Concert Orchestra. Combine all of that, and you get the "God Only Knows" song and its elaborate music video.
Proceeds from the charity single, available to download  later Tuesday, will go toward BBC's Children in Need charity.
The video stars Wilson creating a new version of the Beach Boys tune, with Elton John, One Direction, Stevie Wonder, Pharrell Williams, Jake Bugg, Lorde, Emeli Sandé, Chris Martin, Kylie Minogue, Paloma Faith, Sam Smith, Florence Welch, Chrissie Hynde, Brian May, Dave Grohl and many more musicians.
"God Only Knows" also features classical musicians Alison Balsom, Martin James Bartlett, Danielle de Niese and Nicola Benedetti; folk performer Eliza Carthy; Senegalese singer Baaba Maal; jazz performer Jamie Cullum; British-Asian musician Jaz Dhami; and the BBC's Zane Lowe, Lauren Laverne, Katie Derham, Gareth Malone and Jools Holland.
The "God Only Knows" project is also helping launch BBC's music initiative, BBC Music.