Will.i.am and Sean Lennon rubbed shoulders with Prince Harry at a glamorous bash in New York.
The royal was the star of a fundraising dinner in aid of US supporters of Prince Harry's Royal Foundation.
The third-in-line to the throne proved a draw to Sean, son of Beatle John Lennon, The Voice judge Will and writer John McInerney, who penned Bright Lights Big City, at Manhattan's famous Four Seasons Restaurant.
"I am a great admirer of Prince Charles and his charity work and I think it is incredible Harry has made it part of his legacy to carry this on. He doesn't have to do what he does, so I applaud him."
Will met the Prince after last year's Diamond Jubilee concert at which he performed.
He added: "He's a party prince, a soldier and a philanthropist. He's a regular guy. If Harry was a movie character he would be Iron Man.
"I grew up watching documentaries about the royal family so I am really pleased to be meeting him."
Speaking about Harry, Sean said: "It's great that he is here. He seems to be really enjoying it. But it seems as if the whole city is running around trying to spot him, so I hope he doesn't think New York is always like this. He is well loved here."
The glitzy night, part of Harry's seven-day tour of America, was in aid of the American Friends of The Royal Foundation of The Duke and Duchess of Cambridge and Prince Harry.