Conventional is not something you could ever accuse Trevor Lock of being. From a fashion sense stuck in the Eighties to his wide-eyed vulnerability, it's obvious that he sets himself apart from the comedy crowd before he even utters a word.

His style, too, is distinctive - delivering not so much jokes as tiny fragments of jokes, which are then repeated again and again, each time with some subtle variation.

This deliberate form of anti-comedy, deconstructing gags into almost nothing might have some detached, artistic merit – but it's difficult to buy into, especially in a longer set. The delivery almost goes out of its way to antagonise an audience expecting jokes, and the material doesn't provide quite enough reward for sticking with it.

His chief affectation is a stop-start delivery, continually tripping himself up or correcting himself after almost every phrase. The effect is to produce stream of weedy gags tumbling over themselves, perhaps in the hope that enough barely-funny lines can combine to make a really good one.

Take, for example, his description of a mugging: 'He pulled a knife no it was a fork no it was a spoon he said, "show me the money" I thought he said, "show me the monkey' And on it goes.

And just in case this style builds up any momentum, he brings it all to a grinding halt with a 'No, that didn't happen' after almost every other line. Once or twice, it's funny, but it's a trick so overused it becomes difficult for the audience to invest any attention in stories even the comic appears to have little faith in. It may be a contrivance, but it's a bit too convincing.

What's frustrating is that from this babble of non sequiteurs, some very fine jokes do emerge – clever, surreal wordplay, mainly.

There's also an undeniably endearing charm to his faltering, innocent persona that you really will him to succeed, against the odds.

But, after nearly a decade in comedy, he still struggles to harness his uniqueness into something a bit more reliable in delivering laughs.