BD: You are also doing a sitcom for BBC3 called Josh, directed by the comedian David Schneider. Is it at all like Seinfeld?

JW: Well it's not a studio sitcom so that's different. Basically I've always wanted to do a sitcom but never had the guts. In stand-up you are in control and it's very meritocratic. If you are good and the gigs go well you will rise up. I liked that feeling of control but doing the sitcom is the most I've left my comfort zone. I'd not acted before but I'm playing myself essentially so that's a Seinfeld thing. But this is genuinely the best fun I've ever had doing anything ever, which is dangerous because it makes you want it to happen more. Yes, David Schneider is directing. He was interested in getting the best performances out of us, but a lot of the time all I could think about was 'I'm being directed by Tony le Mesmer from Knowing Me, Kbowing You...with Alan Partridge.'

BD: How did it come about?

JW: The producer came to me and said 'I think we could do a good sitcom about your stand-up character and his life' so it's a kind of appropriation of that. I don't know if there is anything in the first draft that is in it now, but it's probably the thing I'm most proud of, maybe even more than The Last Leg. I can't believe we've created this from nothing and it's now this thing. The cast is really good and I hope it feels fresh but I'm the worst judge of my own thing. I'm writing it with Tom Craine, he's a really great writer who works on The Last Leg as well.

BD: Elis James and Beattie Edmondson play your flatmates and Jack Dee is your landlord called Jeff? 

JW: I know Jack and cheekily asked him if he wanted to do it. He was mindblowingly brilliant. He's a proper character actor. He'd say 'that bit where Jeff picks up the drink I don't think he'd drink that, I think he'd drink this'. I'm still at a learning stage so the one thing I wanted to do was surround myself with people I feel comfortable with, proper actors. Elis is a good friend. When we had both split from our girlfriends he would sleep in my double bed with me when he was in London. I think I offered it once then suddenly he always stayed at mine. You can share a bed with your mate in real life but put it in a sitcom and people go 'no way' or it's too Morecambe and Wise. 

There is a weird thing casting Jack Dee, who I watched when I was growing up. The most amazing thing about doing this job is is you more or less get to meet all your heroes. In Edinburgh I was in the same venue as David Baddiel so we'd just meet and have a normal chat and I'm thinking 'you're the guy that..' You kind of cut yourself off quite quickly, he doesn't want me to go 'you know that episode of FFL with Brigitte Nielsen…' I'm on Danny Baker in a couple of weeks, I called into his football phone-in when I was 13 on Radio 5. My call wasn't very good but he turned it into something and saved me.

BD: So the sitcom is an online pilot which will then go out on BBC3. And then hopefully a series?

JW: Everyone seems hugely positive but it's the hope that kills you. I've built my whole career on thinking nothing good will ever happen then you will be pleasantly surprised when it does. Every day there is something exciting. It's bizarre to compute that you are still getting away with this. You don't ever get to a place where you go 'I'm there now'. Successful people are just as neurotic as I am. As they say in football winning your first League Championship is not the difficult bit, it's winning the one after that's toughest. 

BD: The only bad thing that has happened to you recently is the sudden death of Addison Cresswell, the founder of the agency you are with, Off The Kerb, just before Christmas.

JW: It's been horrible. It's just your mate who has died. You see the news reports but at the end of the day he was the most exciting, funny, entertaining...far funnier than anyone I've ever met, any person I've ever spent any time with. It is absolutely one of the worst things I've ever been through. There were lots of lovely things written about him, Danny Baker wrote a tweet about how that kind of energy is gone. I feel I'm so so glad I got to meet him because literally whatever happens I will never meet anyone like him again. He loved the role that he was this kind of fixer. I had a bad neck and he was 'I know an osteopath, I know a plumber'. It's been weird, it's not back to normal but it has brought everyone together to do this for Addison. The first episode of The Last Leg was fine until the card came up at end, dedicating show to him. It's tough. I still think about him all the time. 

BD: The whole comedy industry was shocked by his death. 

JW: It was so unexpected. I saw him on Tuesday, spoke to him on Thursday, saw him on Friday and he was exactly the same. He was trying to convince me to come back from holiday to do a TV show. I said no and he said 'ah well, I try my luck, that's what I've built my career on'. It just felt like it came from nowhere two days before Xmas. The myth will now build, but it's not going to replace him. A book about Addison would be better than a book about any comedian there is. They will have to get Michael Sheen or Steve Coogan to play him in a film. 

Josh Widdicombe is currently on tour. Details here.