Ross Noble, Edinburgh Playhouse

Call a comic surreal and you hand him or her a licence to be as self-indulgent as they desire. Think of Vic Reeves, who long ago started believing that the mere proximity to one another of words like "bacon", "kazoo" and "Manama" was sufficiently hilarious to bring down the house. Ross Noble is, we are frequently told, a surreal comedian. His new show certainly contains enough references to "dwarves in sombreros" and "shaven suicide monkeys" to ensure that its title, Nonsensory Overload, comfortably adheres to the terms of the Trade Descriptions Act.

As befits a show with a get-out clause for a name, Nonsensory Overload isn't guided by a narrative arc so much as by a fatally fused Sat Nav. Like Billy Connolly, with whom he shares not only a penchant for motorbikes and being filmed wandering around the Antipodes, but also a similarly haphazard comic style, Noble is his own concept, and his show contrives to appear as though it's one long digression. Last night it took him two-and-a-half hours to tell the story with which he started the evening, about a family funeral.

What lifts it above an exercise in mere randomness, and what makes it at times devastatingly funny, is the terrible kind of logic Noble brings to the world he creates on stage. When he zooms off on riffs about the Nando's Wizard or the Googlephone – “It sounds like a bizarre German brass instrument: ‘Klaus, bring out ze Googlephone’” – one can not only see the bizarre contraption materialise magically before one's eyes, but one can also appreciate how, by sheer force of imagination, he has managed to drag us with him to the point where it all seems perfectly rational.

One goes along for the ride knowing that, while some roads will lead to the comedy equivalent of Fifth Avenue, others will end in a cul de sac. When he succeeds in joining the dots on the map he can be dazzling. A rant on predictive texting – “like hanging around with a pissed gypsy” – leads to him picking up the strands of an earlier routine about “ghost love” which, having originally featured Patrick Swayze, Noble then takes to even more depraved lengths involving knitwear and Werther’s Originals.

There are several other wonderfully inventive leaps and some excellent physical comedy, but at other times he seems simply to be treading water. Calling the Pope “a dick” and having a pop at sexy vampires is a bit lame, while last night's interaction with the audience member sporting the PUBES T-shirt (it’s a long story) got less funny and slightly more uncomfortable as the night wore on.

And wear on it did. In terms of marathon gigs, Noble is the Bruce Springsteen of comedy, and the rogue phone-glancer in the front row whom he spotted surreptitiously checking the time was merely acting out what many of us were thinking. He's on stage far too long, especially for a comic who admits at one point that much of his act feels like watching “a confused man being poked with a stick”. The set – like a scrumpy-infused homage to CBeebies' In the Night Garden, festooned with over-sized inflatable ducks and octopi – suggests something more along the lines of a giant, gifted, attention-deficient child enjoying an extended soft-play session. Which is to say that Nonsensory Overload is frequently very funny, and often clever and surprising, but just a little exhausting at the same time.

• Ross Noble on tour until 13 December. Find tour dates on his website
  
• Ross Noble is Pro-Live on theartsdesk
• Find Ross Noble on Amazon