Last week, Simon Cowell announced that he was organising a charity single for the victims of the Grenfall Tower blaze.
Since then, a bunch of stars have been seen leaving the Notting Hill recording studio in London, and speculation has been mounting as to who is going to feature on it.
According to MTV UK, there's a long list of stars that will lend their voice to the cause.
Their list consists of Angel, Anne-Marie, James Arthur, Carl Barat, James Blunt, London Community Gospel Choir, Ryan De La Cruz, Roger Daltrey, Craig David, Deno, Celine Dion, Donaeo, Mr Eazi, Ella Eyre, Paloma Faith, Shane Filan, Matt Goss, Tom Grennan, Jessie J, Louisa Johnson, Kelly Jones, Labrinth, Leona Lewis, Dua Lipa, Gareth Malone, Brian May ,Tokio Meyers, 5 After Midnight, John Newman, Rita Ora, Liam Payne, Gregory Porter, RAYE, Emeli Sande, Shakka, Jorja Smith, Dan Smith, Matt Terry, Louis Tomlinson, Tulisa, Jessie Ware, Robbie Williams and WSTRN.
Other stars such as Geri Horner, Fleur East and Jess Glynn were spotted leaving the studio too.
Producers at the studio are said to be working tirelessly at Sarm Studios on Ladbroke Grove in a bid to get the single ready for release by 8am on Wednesday 21st June.
The track will be a cover of Simon and Garfunkel's Bridge Over Troubled Water.
Artists For Grenfell charity single - available for download on Wed from 8am. Exactly a week after the disaster. It's sounding incredible 👍— PHILIPPA TOMSON (@PipTomson) June 18, 2017