"That was a great take," says Greg James at the end of his recent video with Taylor Swift.

It's safe to say a few people agree.

Within eight hours of going online the clip, which sees Greg and Taylor miming to her latest single Blank Space in the back of a people carrier, became the fastest-ever Radio 1 YouTube video to reach one million hits.

But as seamless as the final product may be, the behind-the-scenes video proves it wasn't a one-take wonder.

So how did Greg avoid an awkward silence with one of the world's biggest pop stars for a whole hour?

It involves smuggling her out of Radio 1 then talking about cricket, giraffes and doing impressions of a pilot - obviously.

When you see Taylor interviewed, she always just seems like the loveliest person ever. Can you please start by confirming that she is?

"I am here to report that she is one of the loveliest people I've ever met, and one of the most grounded as well.

"We were in that car for an hour or so in total.

"We chatted, and that's on the behind-the-scenes video. I have never met anyone who is so famous but so normal and interested in you.

"She's remembered that when we met a few months ago I'd told her I was about to do a half marathon - she was like, 'Oh, how did the marathon go?' That's the biggest pop star in the world!"

I think a lot of people look at Taylor and think, 'You know what, if I was ever to meet her we could totally be best friends'.

"Completely! I completely want to be friends with her! She's fun, that's the main thing.

"For her to say yes to sitting in a dodgy hatchback with me, being driven round London, that says it all really.

"On the day, we had to escape out of Radio 1, because there were paparazzi outside. So we sent a decoy car out of the loading-bay."

With a fake Greg and Taylor inside?

"Haha, no it had blacked-out windows. Meanwhile, we were creeping down the back stairs of Radio 1, down the fire escape, out the back door into a waiting people carrier.

"We were whisked off to Lords Cricket Ground, where the car on a trailer was meeting us.

"It was all timed to precision because she was recording Graham Norton that night.

"There was a police escort so we could get a smooth take - they stopped the traffic a couple of times. It was absolutely brilliant."

And what do you chat about with the biggest pop star on Earth? You've got that awkward moment when the crew go "it's going to be 10 minutes" - you turn to Taylor Swift - what do you say?

"Well, erm, we talked about … cricket?"

Does she like cricket?

"Doesn't know much about it, to be honest.

"But I informed her about Kevin Pieterson, who was on Graham Norton with her that night.

"She actually mentioned to him later that she'd been at Lords that day. And called him Peter Kevinson by accident."

"We talked about what house she's going to buy. She looked at all these nice houses by Regent's Park and went "I want that house, who lives there?

"I said, 'I think that's probably the American ambassador'."

She could still buy it

"We drove past London zoo and I pointed that out. '[I told her]You can probably see the head of a giraffe there'.

"I started doing my pilot voice into a walkie-talkie.

"And she also sorted out all the technical difficulties. I couldn't work out how to work the sound recorder.

"She grabbed it and went "it's not working because you haven't turned the volume up. So I'm an idiot."

Was there any point at which you got carried away and were tempted to ask for her number?

"Haha, no I didn't want to push it. Even though the lyrics of the song were 'I've got a blank space baby, and I'll write your name', I didn't at any point think she was singing that to me.

Perfect in-line if you'd wanted to…

"Yeah, I should have presented my phone, and gone 'I've already put Taylor S in, here you go…' I wouldn't do that.

"It was professional. Fun and silly, but professional. I didn't want to embarrass myself - I've been in that situation too many times before."

And the video's gone mad!

"I know. I really am so pleased that people like it. I love the idea of normalising pop stars and putting them in situations where they wouldn't normally be.

"It's brilliant to remember that these people are… people. Because she has this mad life but does normal thing."

She makes cookies!

"Yes, very useful on a long journey actually. She'd bring all the baked goods and everything."

And fix your stereo…

"I've reconsidered. No, I do want her as a girlfriend."

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