Macklemore. You know Macklemore right? Yeah, you know that guys face. How about his collaborator and producer Ryan Lewis? No, you have no idea what Ryan Lewis looks like, do you? Well, Jimmy Fallon made his mission to find out and sent the real Ryan Lewis out to ask people who he was, during a hilarious episode of The Tonight Show.

Ryan lewisRyan Lewis performing with Macklemore at Wynn, Las Vegas [Photo: Getty Images: Credit: David Becker]

"A lot of self-confessed hip hop fans wouldn't even recognise Ryan Lewis if they were standing right next to him and talking to him," Fallon said. "Which is why we sent Ryan Lewis himself, no disguise, out to the streets of New York to ask people what they know about Ryan Lewis."

On the streets, Lewis was dismayed to find that one girl failed to recognise him even after he showed her a photo of him and Macklemore together. Another man said: "Don't really know what he does. He's like a package deal though; he comes with Macklemore a lot."

"I can't think of what he looks like," one girl said.

More: Macklemore and Ryan Lewis partnering with Broadway show

"I thought he was a producer. I always see him on-stage when Macklemore's performing. It seems like he does with computers and what not. I've got no clue," he said.

"He's the back up right?" asked another girl.

At the end of the video, Macklemore came to the rescue - or so we thought. When quizzed by his producer buddy, the superstar rapper said he had "no idea" what Lewis did.

Macklemore and Ryan Lewis have shifted millions of albums, won four Grammys and scored a global number one hit with Thrift Shop. 

More: watch the video of Ryan Lewis asking "Who is Ryan Lewis?"