Simon Munnery: Renegade Plumber (4 stars) | Spencer Jones: The Audition (4 stars) | John Kearns: Don't Worry They're Here (4 stars)

Simon Munnery once told me in an interview that if he liked a joke and it worked 10 per cent of the time it stayed in his set. Which pretty much sums up what makes him stand out as a comedian.

It's impossible to imagine the Fringe without him these days. From his Perrier-nominated League Against Tedium show in 1999, through Simon Munnery's AGM and being arrested on the Royal Mile at 3:00am in 2000 for dropping his trousers on Arthur Smith's alternative tour, he's been causing a stir somewhere for much of the past couple of decades.

He's also fond of his eccentric props but, unusually, his latest show Renegade Plumber looks stripped down compared to some of his previous efforts. It seems he's been putting his energies into one prop in particular this year, or rather one invention. In an attempt to try and keep his Australian wife warm when camping in the UK, he's been fashioning a heater with the use of a camping stove, pipe, and saucepan. Think a comedian can't find a way of making that funny? Well, you've clearly never seen Munnery. Even the plumbing system diagrams get a big laugh.

The key to Munnery's success and eclecticism seem to be his continual indulgence in his interests, and those interests are wide ranging. Aside from engineering he also treats us to a rendition of the protest song Mrs Barbour's Army – just because he likes it. There is however some observational humour here too, which dips a toe into the political, from the cutting of archaeology A-level to Grenfell Tower. He always manages to make a pertinent point and still end on a high note. This show is early in its run and therefore still pretty loose – he's still clearly working on it. But Munnery's inherent innovation makes him a Fringe must-see nonetheless.

Though he has fewer Edinburgh shows under the waistband of his tights than Munnery does, Spencer Jones is fast becoming an unmissable act too. Also a lover of invention and props, he's once again armed with his loop machine, an eccentric haircut and a huge array of apparently unrelated bits and bobs. The gentle theme is that Jones is attending The Audition, which despite being for a "job interview for dickheads", is something he's pretty excited about.

With his Tommy Cooper grin and some eclectic wardrobe choices, he's a wonderfully endearing character – whether he's calling himself Spencer Jones or The Herbert. Given the amount of technology in the show and the number of objects that are glued precariously together, things often go wrong in a Jones show, so this year he's ready with a jingle to cover it. 'Something's Gone Grong, Something's Gone Wrong' just adds to this show's loveable qualities.

This year he's also got too many tennis balls—there's an added humour in imagining him sitting at home glueing googly eyes onto them—as well as some nonsense with a vibration machine and some particularly cute moments involving audio of Spencer talking to his young son about where adults come from.

The sum total of John Kearns's props are his trademark tonsured monk wig and tombstone teeth. Oh, and there might be another later on but we won't give that away. As ever Kearns mixes the laughs with a gorgeous melancholy in his latest offering,Don't Worry They're Here. He's upset by the sudden post-race death of the Grand National-winning horse Many Clouds, which he may or may not have placed a bet on. Even a Creme Egg can't console him. His friend Mehmet in the café tries to cheer him up but will anything succeed in getting his mojo back?

There are some evocatively imagined set pieces here, such as Jeremy Corbyn's bathing habits and Kearns's day dream of a sweet shop, should he ever own one, with vintage posters, straw boater hats and a pretty girl behind the counter who would laugh at his jokes. Kearns draws you into his strange, slightly dissatisfied but sighingly beautiful little world, once again creating a lovely hour of deceptively low-key humour. The bittersweet yet strangely warm feeling will stay with you as you wend your way into the evening.