Now I don't need to be drunk to be happy

He wanted to go to drama college but his grandparents had been not very successful actors and his mother persuaded him to get a vocation, hence his foray into the catering industry.

"I really liked it," he says. "I met lots of people I liked there, too. Most of them were waiting tables during the night and going to Rada by day. Then one of them said I should be on the stage and I thought 'Why not?' so I went down to the Comedy Store and did an open-mike session, where the audience take over, and that was it."

He wasn't nervous, he says. "Once I was doing it I felt compelled by it. I loved it - being on stage, having that microphone. I felt it was where I was meant to be. I do still feel a compulsion about it all."

But the drinking? "Once I started doing stand-up, I stopped. It was not possible to go on stage drunk. You have to be clear and with it because you have to be able to see what is working and what isn't. If you're on a riff about something and the audience is not buying it then you need to wrap up and move on very quickly."

So how did he stop? "I nearly always do things because someone else suggests I should. I went on stage at someone else's suggestion. I ended up gigging because someone else asked me where else apart from the Comedy Store I was doing stand-up and it hadn't occurred to me to try anywhere else. I am very motivated, though, once I've started something. But the drinking was a decision I took so I went to AA but it didn't work out."

Why not? "It was trading one addiction for another. I found it depressing and useless for me. I need to keep active to keep going. I have to have my body and mind in balance. Like if I'm writing, that's all I want to do. I am obsessive like that so when it came to alcohol I kicked it by keeping busy, performing, that type of thing."

So does he drink now? "Yes I do drink," he says. How much does he drink? " Actually, I don't think I drink too much. I would say it was moderate but other people would probably say that I do drink too much." Does that bother him? "No," he says, scornfully. "If it bothered me, I'd stop."

He also has his family who keep him pretty much on the straight and narrow. "I met my wife Jane before I was a comedian,"-he says. "I waited at her table and we became friends." They got married two years after they met and now have four children - Hattie, 14, Phoebe, 11 and their twin boys, Miles and Charlie, who are eight.

When Dee talks about his children, his natural grumpiness tends to reveal a softer underbelly and yet he's still a mass of contradictions about them. He'll tell you how much he likes being a dad.

"I like being around then. They're fun," he says. In the next breath he'll tell you how, when they were little, he was desperate to get away from them. "There were so many of them and so quickly!" he says. "It was exhausting. I think I went on tour to get a rest. The car would come to take me to the theatre and I'd get in, heave a sigh of relief and go to sleep until we got there."

What about his wife? Did she ever get a break? "No," he says. "She's spent her life looking after me and the kids. But I miss them now you know. I think being a family man and a father stops depression.

"That's why I don't like to tour as much. When I was starting out doing standup, all these comedians were out having a good time at night and I missed all that really. I went home to the kids but I'm very glad I did. I've never been clubbable at the best of times but I wouldn't have wanted to hang around night and day with a group of comedians. Can you imagine how depressing that would be?"

For a man who is so funny - and I think Jack Dee is truly one of the funniest comedians around, Lead Balloon had me crying with laughter in my arm chair - he can be relentlessly dour and tricky, but this family life has obviously touched him deeply.

"I'm very glad I met Jane before I became successful," he says. "We had no idea then - I wasn't even thinking of being a comedian so she has known me and I have known her through it all. I take a lot of reassurance from that idea really. You know, we'll be in the supermarket and people will turn to her and say, 'Isn't that Jack Dee?' and she says, 'Never heard of him' and that makes me laugh."

He tells me he is very proud of Lead Balloon, as he should be. "A sitcom is like a Holy Grail for comedians," he says. "I had no idea if an audience would relate to Rick and the people around him but the ratings have been good on BBC4 so ..."

He's very caught up in the characters and says that he and Sinclair spend hours giggling away devising 30 jokes a day. "It's not like that really," he says, "but it's very good fun to do." And then he smiles and his whole rather squashy, rather handsome face, lights up.

Lead Balloon is on BBC2, Thursday at 9.30pm.