Rhys Darby: It's Rhys Darby Night

Given how well-loved the character has become, it seems perhaps unnecessary to introduce Rhys Darby as Murray from Flight of the Conchords. It would be yet more redundant to point out just how much hype there is surrounding his Edinburgh run. But, for a while, it seems like Darby might just live up to it.

He's introduced tonight by Bill Napier – a gruff, slightly toop park ranger from New Zealand, with some mildly threatening self-defence techniques. He chats about Rhys, and prepares the star's set: shirt – check; comedy glasses – check. At the risk of giving the game away, it's Darby in disguise – well, a hat. In fact, it's a clever ploy, allowing Darby to talk about his new-found fame, about smalltown New Zealand communities and about the conventions and expectations of a comedy show from a slight remove. He's on secure ground here: his material is thoughtful, engaging and very funny.

Sadly, not all of his set is as thoughtful or engaging. Or as funny. Too often, jokes build up nicely and then fail to deliver a punchline. The first of two character sketches is tedious; the second, redeemed only by a calm shooshing of the audience – a gag which works only because he has the guts to draw it out for impossibly long, not because of the preceding yarn. Darby's machine and dinosaur noises are fun but, if they are meant to unite a disparate set, they fail to do so.

It's clear that Darby is a very skilled entertainer. An increasingly useful comparator this year is how comics handle the regular firework volleys or jet fly-pasts which are only marginally deadened by the thin hide of the purple cow. Loudly interrupted midway through a mock phone conversation, Darby ad libs beautifully, feigning realisation that the call to Beirut is "costing him a fortune". But if as much care had been spent on the set as the advertising materials, this might be something much more refined.