Forty years on from the release of Do They Know It’s Christmas? BBC4 documentary unearths 75 minutes of rare and previously unseen film footage from the day of recording

The images shocked people around Britain, including Irish singer-songwriter Bob Geldof, then best known as the frontman of the Boomtown Rats – and he decided to take action.

With Midge Ure, the lead singer of Ultravox, he wrote the song Do They Know It’s Christmas? Then on November 25, 1984, they gathered some of the biggest names in UK and Irish pop to form the charity supergroup, Band Aid, and recorded it in the course of just one day.

The plan was to raise money for the victims of the famine, but Do They Know It’s Christmas? exceeded everyone’s expectations.

It went to number one, would hold the record as the UK’s the fastest-selling single for well over a decade, and is still heard on the radio and festive playlists every December.

Although no one involved knew quite how historic that recording session would be, cameras were there at SARM Studios in Notting Hill to document it. Some of the footage was used for the iconic video, but some of it has never been seen – until now.

The Making of Do They Know It’s Christmas? unearths 75 minutes of that original footage, shot on 16mm film and newly restored and digitised.

It features rare and unseen moments in which stars, including Bananarama, Boy George, Glenn Gregory of Heaven 17, Paul Young, Phil Collins, Spandau Ballet, Sting and more, rehearsed and recorded their parts.

There are also interviews that were shot on the day with Bono, Gary Kemp, George Michael, John Taylor, Simon Le Bon and Trevor Horn.

For Bob Geldof, the fact that no one realised just how momentous an occasion it was all is part of the documentary’s charm.

He says: “That Sunday morning when a bunch of young spotty English pop stars who were (more or less) just out of school and had taken over the pop culture of the world, ambled up a Ladbroke Grove street in London to make a song their friends had written for the starving people of Ethiopia, they could never have understood the enormous consequences of that day…

“This then is the ‘fly on the wall’ story of that day from found footage that no one had thought to look for before, but is now an integral part of British pop history. I love it because it is so… English. So guileless, so charming and yes so innocent.”

The song would inspire other charity singles – including the USA for Africa song We Are the World, as well as later remakes of Do They Know It’s Christmas?, but the magic of the original is hard to replicate.

As Bob says: “Compare and contrast with the American follow up and it’s hyper-sophisticated, hyper super-talent, hyper-organised and professional and our lot, basically a bunch of bouffanted oiks giving it large and being quite brilliant.

“What wonderful people they were. And largely still are. Great film.”