Miley Cyrus has made her first appearance as a guest mentor on American Idol.
The 17-year-old star gave advice to the 11 remaining contestants in the popular talent show on Tuesday.
The hopefuls all had to sing songs which had been a Billboard Number One - which is the same as being top of the charts in the UK.
Hannah Montana star Miley is also due to perform her latest single on the results show on Wednesday night.
She'll be joined in the results programme by fellow teen stars Joe Jonas and Demi Lovato.
Miley has a new film out too - it's a romance called The Last Song and her love interest is played by her real-life boyfriend, Liam Hemsworth.
Miley is the first guest celebrity mentor on this year's American Idol, although Victoria Beckham and Shania Twain have been guest judges.