Pop superstar Madonna gave fans a special treat at a secret gig on Wednesday - by bringing Justin Timberlake onstage to sing with her.
The 'Material Girl' was performing for a select group of fans at New York's Roseland Ballroom to celebrate the US release of new album 'Hard Candy' when her surprise guest was revealed.
During the 40-minute set - the first time Madonna had performed tracks from 'Hard Candy' live - she was joined by Timberlake for a performance of single '4 Minutes', which they had collaborated on.
After thanking Timberlake for joining her, Madonna told the crowd she felt "like the luckiest girl in the world to be able to make a record with him, Timbaland, Pharrell (Williams), Kanye West.
"And even though I've made what seems like 100 records, every time I put one out it's like the first time, and the best time."
And the kind-hearted star rewarded fans who didn't manage to obtain tickets for the free show by streaming the performance online, reports GigWise.com.