Tall storeys

"It's a show I was very passionate about, so when it finally came on DVD I wanted to give it as much publicity as I could get," he says during a stopover in Newcastle.

Diplomatically, he keeps his thoughts about the BBC's treatment of the show to a minimum, except to say it commissioned two series and failed both of them.

"In organisations like that, decisions are made," he says philosophically. "It was scheduled at strange times and moved around. But it has a shelf life on DVD, and the interest from people is as great as it was on TV."

15 Storeys High has found a loyal following and achieved cult status.

Lock stars as flat owner Vince with Benedict Wong as his new lodger in the tower block in South East London. From time to time the action switches to other residents and their peculiar habits. Written by Lock, together with Mark Lamarr and Martin Trenaman, the series was nominated for a Bafta.

Lock took risks to make something original and distinctive, and you can't deny that 15 Storeys High is no ordinary sit-com. "I worked very hard on every aspect. It was a year's work and I'm very proud of it," he says.

"I've done a lot of light entertainment on TV in the past few years but the most frequent thing people say in the street is 'I really liked your show 15 Storeys High'.

"People feel quite personal about it. They've discovered this thing that had been cast aside. Everyone who was into it has a degree of passion about it."

It began as a 15-minute pilot show on BBC Radio Four, was developed into a series and then Lock wanted to turn it into a narrative piece. 15 Storeys High the TV series was born.

"Writing a good television sit-com is the most difficult thing to do. It's the least valued and the most difficult," he says.

The experience hasn't putting Lock off having a go at another TV comedy series in the future, although not straight away. "It's harder but more fulfilling when you pull it off," he says.

Luckily, he was able to go into entertainment after the 15 Storeys High experience. Among other things, he's a regular team captain on C4's Eight Out Of Ten Cats, which returns this summer.

"Panel shows keep you working in the business and still doing comedy. They're very good for loosening up the mind because you have to be spontaneous and on the ball," he says.

"I have young children and those shows mean I'm not on the road or locked away obsessed on personal projects."

There was also a film script he wrote for Johnny Vegas that didn't get made. "That's not unusual in the world of writing scripts, 90 per cent don't get made," he says.

He's trying again with another script for Film Four about stand-up. "I don't think it's been properly represented in film and drama. Other writers don't like us because they see us as so cocky - either that or as tortured clowns or soulless, gutless egomaniacs," he says.

He's also writing himself a stand-up tour to take on the road this autumn.

He didn't always want to do comedy, not getting into it until his mid-twenties. "I think I wanted to perform in some way but travelled, worked on building sites and then got into drama school on a rough diamond ticket really because I hadn't done any acting," he recalls.

"After a year I realised I didn't want to be an actor. I had to be thrown out because I had a full grant and if I'd just left I'd have had to pay it all back."

He drifted back into his old lifestyle until getting caught up in the stand-up circuit that was building up at the time. "It was easier then, it's really tough starting out in comedy now," he says.

"I'd been looking for it without realising it. It's a great lifestyle. I'm one of those moany comedians but really you have eff all to moan about."

15 Storeys High (15) is released to buy on 2 Entertain, £24.99.