Rubberbandits, Soho Theatre

Rubberbandits embody that modern entertainment industry phenomenon – a huge YouTube hit who have moved into the mainstream with ease. The prankster hip hop duo – Mr Chrome and Blindboy Boatclub (aka Bob McGlynn and Dave Chambers) – have notched up more than 25 million hits online and now routinely sell out their energetic live shows, which they perform as if music gigs.

They started life as underground artists, ripping the piss out of Irish culture and politics, and perform with shopping bags over their heads – as if either delinquents keeping their identity secret from the social in their home town, the “dark and dirty ghetto that is Limerick City”, or plastic terrorists in the IRA mould. At one point the pranksters were so underground that (reputedly, at least) drug dealers in Limerick were selling their CDs alongside hash, as nobody knew where else to buy them.

The duo's lampooning is usually spot-on and they never go for the obvious joke

Their material is written with an ear for both hip hop's rhythms and its complicated rhyming structures, and we're reminded immediately that they're no slouches on this front. "We're not comedy. We are hardcore gangsta rappers,” Mr Chrome tells us, even if some of their dance moves are less than fluid.

Then he announces there will be three jokes in the show - which equals the number of times they laughed at a Jack Whitehall DVD. Whitehall isn't the only person to have a slyly funny dig made at him, as their superb guying of self-proclaimed hard man Danny Dyer - “Liar Liar, Danny Dyer/Get him in a headlock, who's the hard man now?” - attests.

Aided and abetted by a rubber-masked Willie O'DJ on the tables and with expertly made videos playing on a screen behind to give extra substance to the jokes, they ran through some of their greatest hits last night. "Horse Outside" is a rather sweet love song about an Irish lad's favoured form of transport to woo the ladies and outdo other guys' wheels - ”Fitzy drives a Mitzy... Enda have a Honda...”; "Pure Awkward" recounts the time Blindboy Boatclub had a misunderstanding with another rapper when he was on holiday in Los Angeles; while “Black Man” (“I need a black man in my gang... doing black man thangs”) hilariously skewers any number of Hollywood stereotypes about gangs and ethnicity.

It's not all funny, though. A song about having sex with a fat girl is crass, while "Up Da Ra" (in which everyone from Dylan Thomas to Sharon Stone is claimed to be a member of the IRA) doesn't quite cut it as satire. But the duo's lampooning is usually spot-on and, as they prove with “Spoiling Ivan” - about Mr Chrome's friendship with a six-year-old-boy - they never go for the obvious joke. 

• Rubberbandits are at Soho Theatre, London W1 until 27 July; then at Gilded Balloon as part of the Edinburgh Fringe 31 July-26 August