'A quick set? You haven't got a quick set! And what do you mean, "the bigger acts"? Any act in the world is bigger than you! That fella who plays the spoons down the tube station is bigger than you!'

'It'll be fine,' says Colin, waving away my concerns. 'It's just talking ...'

But it is not just talking. It is set-ups, and punchlines, and callbacks, and pay-offs, and ... you know ... jokes. But Colin already has one of those, apparently.

'I've been working on it a while,' he says. 'It'll be good to give it a public airing.'

'You've written a joke? When did you write a joke?'

'During the Beijing Olympics. But it remains topical. It goes like this ... '

He casts a nervous glance around, just in case there are any lesser comedians listening in who might be short of a topical joke about the Beijing Olympics.

'So ... I'm not racist,' he begins, before adding: 'I love the hundred metres!'

He sits back in his chair, arms out, proud of himself. I remain open-mouthed.

'Are you sure you can make that last five minutes?' I ask.

'Relax, Dan. Everything's going to be fine.'

'But there'll be an audience! What if they don't laugh?'

'I'll riff! And anyway, there's no such thing as a bad audience,' he says, wisely. 'Only bad comedians.'

I can't believe Colin is using words like 'riff' and already counting himself among the 'good' comedians. But twenty minutes later, as he sees his audience of real, actual people starting to make their way downstairs, he realises his mistake.

'What the hell am I doing?' he says. 'I can't make one joke last five minutes!'

'I don't know!' I say, just as panicked. 'Why are you doing this?'

'Quick - give me some jokes!' he says. 'Anything!'

My mind goes blank. I can remember not one funny thing anyone has ever said, ever. But then something occurs to me. I grab a napkin and get a pen from my bag.

'What are you doing?' says Colin.

'It's an Emergency Joke. You can do it if you get into trouble.'

I can sense Colin is rolling the words 'Emergency Joke' around in his head. Psychologically, he now has a crutch. Something to fall back on. He seems brave once more.

'Let's do this!' he says, tucking the EJ into his back pocket, and we walk downstairs.

Inside, the compere has begun, and the crowd is loving it. He banters, he joshes, and the first act enters to huge applause. She is excellent. I can feel Colin bristling next to me, every now and again patting his back pocket for reassurance.

'So, just before the interval,' says the compere, 'let's all have a big hand for a newish comedian who'll be trying out some material tonight ... Colin!'