A few years ago the concept of Doc Brown winding up on the comedy circuit seemed about as likely as Peter Kay joining Public Enemy. The gifted rapper (Brown, not Kay) was making a decent noise on the hip-hop scene, bagging a particularly sought-after role as one of Mark Ronson's live vocalists alongside the likes of Amy Winehouse and Lily Allen.

The post-Ronson return to normality proved tough, however, and Brown (real name Ben Smith - he's Zadie's brother) was all set to give up performing and get a proper job when an improbable job at Radio 4 thrust him back on stage. He's since supported Ricky Gervais, done a full Edinburgh show and become a sought-after actor, too, with roles in the much-hyped BBC drama Hunted, Gervais' divisive Derek, and as a drug dealer in The Inbetweeners. One to watch? You probably already have.

Can you give us a quick synopsis of how your live show works?

It's just stand-up really, it's generally the people who haven't seen me that think it's something bizarre or gimmicky. I come from a rap background and so I talk about that in the same way that you would if your previous job was a milkman. It's impossible to talk about without demonstrating, so occasionally I do a little rap to tell the story. If you wanted me to sum up the whole thing it's like stand-up featuring jokes that rhyme. There you go.

How did you get into comedy?

I was working for Radio 4 on a couple of different comedy shows and they invited me down to this radio night where people sort of pitch ideas and read from scripts and stuff, and it's a BBC audience. So yeah, the producers encouraged me to go down and have a bash at stand-up basically so I went and really just retold the story of how I ended up at Radio 4 and how strange and how incongruous it was for me to be there.

You know it was specifically for a BBC audience so I wasn't really thinking about writing any universal jokes. I told a story. When I came offstage the guys that ran the venue were like 'ah, we do a proper late night comedy night and I think that improv thing really works and we'll give you £50' kind of thing. I was like 'yeah alright I'll come down and do that.' I think that was probably the next thing I did. So yeah, that was the birth of Doc Brown the comedian I suppose, I hadn't really thought about it until that evening.

It was when I was talking to the two dudes that ran the venue, that was when this guy in a suit came up and gave me his card and I was like, 'whatevs', but then I was chatting to the two guys afterwards and they were like "that's Ricky Gervais' manager", so that was the first time I really thought seriously about it. It was the night I went home and Googled comedy competitions.

There must be more outlets for live comedy than rap in the UK?

Yeah, come on man, the average city has 30 gigs in one night, there's so much going on. You look at the average listings in London for example, you know they're only showing a quarter of what is actually going on.

But before that you were going to give up and get a proper job...

But then I got a call from the dude who I'd met at Radio 1, when I was doing music, who used to host a late night comedy and music show on Radio 1 and he moved into writing sitcoms.

Was that Danny Robins?

Yeah, Danny Robins. He offered me a job just helping him out, kind of like a script consultant on a script that he was working on. He literally just called me to say 'I think you can help. Your writing ability, I think you can do it.' So yeah he just took a complete punt on me, I'd never done anything like that before. So I came in and just helped out really, on his scripts, just tweaking tiny little bits, bits of dialogue, words and phrases, and that ended up being a little job. Then I ended up getting speaking roles on the sitcom that he'd written and worked with him on a couple of other shows, and then you meet producers. I ended up working on three or four different shows for Radio 4.

Did you have a streetwise niche there?

Yeah it wasn't even really a rap thing, Danny was someone who - he'll agree - he was a bit of a fish out of water, kind of a white middle-class dude who'd written a show [Rudy's Rare Records] for an all-black cast. So it was one of those situations where, you know, 'who do I know that's black?' No offence to him whatsoever, it was just one of those things.

It's kind of like you look at the history of Saturday Night Live, there's that go-to guy for the black perspective or the street perspective or whatever, I think Radio 4 were distinctly lacking that. The fact of the matter is they are educated (the audience) and they're generally quite left wing, therefore there is an interest in contemporary diversity: race relations, politics, socio-economic issues, there is an interest there but there's no representation. I think that's kind of why I did well.

You've done some high-profile acting as well?

Yeah, a few little bits, picking up. Acting is a hard gig man, it's hard to get parts for stuff, they've got a very definite idea of what they want the character to look like and it's very rare that they look like a sort of random mixed-race dude. It's a fact of the matter. I would absolutely kill to do more, I love it.

How did you get into it, was it through the comedy side of things?

Yeah, you know you meet casting people, it's all kind of linked to the work I have been doing.

You're also going to be in the new series of Derek - how did that happen?

It came through opening up for him. We have a mutual friend who has been trying to get him to watch some of my YouTube stuff for years. Obviously it was never happening and finally it got to 'alright, fucking hell, I'll watch it,' and he ended up watching, like, everything, and he just called me up and said 'come and open for me.' So we met like that, then he saw me in the flesh onstage and said he was working on a show and would like to crowbar me in. I was like 'hell, yeah.'

Ricky's stuff gets mixed reactions...

If we and he were Americans it wouldn't be an issue, it would be like 'he's amazing'. Over here, we don't really like success or riches. People have turned on him. People arguing against him have said his stuff gets less and less funny, less engaging or whatever. Other people think he's an agent provocateur, and he is, no question.

You need to look at why he does stuff, he's somebody whose heart is solidly in the right place, he's somebody who has no real interest in his own fame. And people might think that sounds strange, but when you talk to him about fame he talks about it so ironically man, and if you look at his work on the Golden Globes, what is he doing? He is absolutely belittling the concept of fame and wealth as being important in life. And if you can't see that then you really have got blinkers on when it comes to Gervais, you're not seeing what he is genuinely about.

Meanwhile you've now diversified into kids shows...

4 O'Clock Club, nominated for two Baftas - season two just started. And Strange Hill High - cool animation, hopefully it should start soon too. Such an ambitious project, the animation is groundbreaking.

One for adults too?

It has the potential. It's cleverly written, funny, genuinely creepy, it revolves around a haunted school. I don't know if you ever watched Eerie, Indiana - I loved that show. There are elements of homage to it, the character I play is called Mitchell, same name.

After working with some big music acts, you worked with some big comedy names on this one...

Great stars: John Thompson, Caroline Aherne, Richard Ayoade, loads of great, great voices. I'm the starring role in it, I'm immensely proud, with those kind of names around me, supporting. I felt like I'd made it when I went up to that room.

To find out more about Doc Brown and his live dates, visit his website: www.docbrown.co.uk

4 O'Clock Club is on CBBC on Fridays at 5:30pm. Guide

Strange Hill High is expected to begin later this season. Guide