Haim say meeting Sir Paul McCartney was “a big deal”.
The group may have won Best International Group at the NME awards this week, but they were even more excited to meet one of their idols.
Despite being successful musicians themselves, they still felt like geeks when they introduced themselves.
“I was like hey Sir Paul my name's Este Haim, I'm in a band and I'm a really big fan of yours, I was super dorky about it,” the singer revealed to BBC Newsbeat.
"I don't normally do that, if I am a fan of someone I'm going to tell, but it's not like I give it out like party favours, so it was a big deal to me."
Haim consists of Californian sisters Este, 27, Danielle, 25 and Alana, 22.
For all three of them, being in the same room as a musical icon was overwhelming.
“It's kind of a bucket list situation when you are talking about a Beatle being in the same room as you," Danielle added to the news outlet.
“I think that might be the most important moment of our lives.”
The icing on the cake for the girls was that the former Beatle revealed he had heard of their band.
They no doubt hope he will listen to the follow up album to their number one debut Days Are Gone, which the group are working on now.
“We are always writing," Alana explained. "We kind of take a long time in the studio so we'll see, it might take some time but not too much."