Robbie Williams and Kylie will be joining loads of singing superstars on Simon Cowell's charity single to help raise money for Haiti.
The song is going to be a cover of the REM classic Everybody Hurts, which was a huge hit back in 1993.
Among the other stars thought to be taking part are X Factor winner Joe McElderry and judge Cheryl Cole, N-Dubz, Mariah Carey and Take That.
A few of the celebs have already recorded their bits.
Mika's one of them and he said it was "a real honour" to be taking part.
Simon said: "I'd like to make this record with as many different types of singer as we can and I hope everyone in the industry comes together to get involved.
Simon Cowell wants as many artists as possible to take part in the single
"The response has been fantastic."
To boost the amount of money raised, the government has also agreed to donate the tax from sales of the single to the fund-raising effort.
Prime Minister Gordon Brown said: "Simon Cowell can make a huge amount of money to help the people of Haiti."