The promotional film, directed by Francois Rousselet from Riff Raff, was created in collaboration with The Mill to celebrate the launch of the BBC's renewed commitment to music, which includes an ambitious wave of new programmes, innovative partnerships and ground breaking music initiatives.

Twenty-seven musical stars were filmed on a green screen, before The Mill's 2D team seamlessly brought them together to appear in the majestic Alexandra Palace. The orchestra was then enhanced with a host of effects created in 2D and 3D including a crystal particle system surrounding Stevie Wonder, Lorde's CG wings, a kaleidoscope of butterflies sitting on Elton John, Kylie Minogue's CG bubbles and an exotic jungle backdrop surrounding the original Beach Boy Brian Wilson.

The Mill's Matte painting team worked on a series of ornate Alexandra Palace backdrops, as well as conceptualising and creating the final ethereal cloud scenes from scratch, which feature fully CG clouds, hot air balloons and the final touch, a small animated feather, seen drifting down to gently rest on Brian Wilson's piano.

VFX Supervisor Hugo Guerra comments, "From the first time we saw the offline of 'God Only Knows' we knew we had a one of a kind project on our hands. Of course, logistically it was impossible to unite all 27 artists in a single day of filming, so we set about planning an ambitious shoot over the course of a year to capture each on of the musical stars.

The sheer complexity of this project has made it one of the most challenging, yet rewarding moments of my career. It's a fantastic watch and still puts a smile on my face every time I hear the song!"

2D Lead Artist Zoe Cassey-Hayes comments, "Due to the scale of this project, it required the input of almost every department at The Mill, using a huge array of software including Houdini, Maya, Nuke, Flame, Photoshop and Hiero to bring it to fruition and create the spectacular final result. This was a incredibly creative piece, from Jamie Cullum flying through CG clouds, to compositing a tiger on Brian Wilson's piano! It was a team effort of immense proportions, involving hugely talented artists and I am very proud to have been a part of such an exciting project."

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