Matt Smith admits "appalling vanity" leads him into "bizarre" situations.

The 29-year-old actor and his 'Doctor Who' co-star Karen Gillan couldn't resist visiting a bar themed around the show when filming in New York recently and the pair are still surprised when they see how obsessed people are with the sci-fi adventure series.

Matt said: "We find ourselves in the most bizarre situations. We attend quite a few 'Doctor Who' conventions. You never get used to driving down the street seeing people dressed exactly like you.

"In New York, Karen and I walked into this 'Doctor Who'-themed bar. It shows the appalling limits of our vanity that we wanted to go to a 'Doctor Who' bar.

"But our curiosity got the better of us. You could have heard a pin drop when we strolled in."

However, Matt - who at 26 was the youngest actor to be cast in the iconic role as the titular Time Lord - is aware people are more fascinated by his alter ego than himself.

He added to Live magazine: "But it's our characters that people are interested in, not us.

"The characters are the stars. I'm lucky enough to inhabit the character for now. But Doctor Who will live on long after I've stopped playing him."