Liam Williams has recently written that gig-ruining hecklers might be a thing of the past, with contemporary audiences considering stand-up to be an artform as worthy of respect as theatre or film. Tonight’s crowd is a case in point. The tail-end of a boozy Friday should attract ill-advised shouting within a packed space but only the odd muffled squeal is heard, Williams stalling briefly to check everything’s fine.

Perhaps the new heckling comes in the form of temperature abuse. Several times, Williams apologises for the room’s excessive heat, which seems unnecessary unless he left the radiators on all day. Appropriate then, that he turns the dial up with Bonfire Night, another ultra-smart and potently funny assault on both modern politics and ancient rituals (the fifth of November gets concise shrift) with dashes of hardcore whimsy, a bit of comedy hip hop (‘sad lad raps’ he dubs them) and some angry meta-exchanges with himself and the Fringe office.

His ‘John Cage approach’ inevitably results in, not exactly silence, but medium-length passages which aren’t always punctuated by a joke to break the tension. The denominator Williams is most interested in is the highest common one, demonstrated early by warning those who have accidentally stumbled into the gig thinking this was Shaggers should leave before they are treated to an hour more akin to ‘sulky lovemaking’.

While his goals are ambitious, the means to getting there can still be blessed with a light touch. He’ll merrily quote European political scientists just before analysing how tricky it can be to operate some tin openers. Climate change is an undoubted bugger but what if it also means we get daffodils all year round? The excitement of Liam Williams’ act is that while you never quite know where you are or who you are listening to, the strength of the material and potency of the gags that do arrive keep things bouncing along with true comedic verve.

Laughing Horse @ The Free Sisters, 622 6801, until 19 Aug (not 17), 11.30pm; 20–30 Aug, 7.30pm, free.