Edinburgh Fringe: Sam Simmons/ Totally Tom/ Humphrey Ker/ Nick Helm

Sam Simmons, Gilded Balloon ****

Sam Simmons clocks a young girl in the front row and stops the show. “How old are you?” the Aussie comic asks. “Ten,” comes the reply, and he suggests to her mother that this may not be the show for them, so they leave. And just in good time, as what follows is a load of cock and balls as Simmons is dressed in vest and pants which, after he is drenched during a gag, become increasingly, er, figure-hugging.

Sam Simmons clocks a young girl in the front row and stops the show. “How old are you?” the Aussie comic asks. “Ten,” comes the reply, and he suggests to her mother that this may not be the show for them, so they leave. And just in good time, as what follows is a load of cock and balls as Simmons is dressed in vest and pants which, after he is drenched during a gag, become increasingly, er, figure-hugging.

But oh my Meanwhile is great fun, a seeming shambles of a show that is in fact tightly choreographed as Simmons reads out emails and letters that people send to him, asking for advice about life, love and relationships, or making comments about his act on a radio station back home in Australia. All the while there is a voiceover and jingles that commentate on the action, or set up gags for which Simmons's actions provide the visuals.

Other jokes have their pay-offs in a series of very funny cartoons on an easel, which are graphic, sexual and scatological, and there's also a shopping trolley on stage - the contents of which provide the ingredients for said soaking and a bread fight with the audience, and a running joke about a box of tacos, which leads to a great physical gag at the end. Surely no Mexican ever digested the foodstuff like this...

But among the madcap action and a show played at a rate of knots - “Are you following the narrative?” Simmons says with a cheeky grin as at least six gags have been run past us in the previous 60 seconds – is an underlying message to have fun and not be cynical. “What does it all mean? Is it art?” Simmons asks at one point. Who cares, because it's just rollicking good fun. Until 28 August

Totally Tom, Underbelly *****

Tom Stourton and Tom Palmer, both 23, have been writing and performing together since they met at Eton, and their complete ease with each other shows in this astonishingly accomplished Fringe debut. The pair created the YouTube hit High Renaissance Man, a glorious spoof about a completely unself-aware rah studying history of art at Bristol University, and the qualities they showed in that film – precision-lancing of their characters' foibles, spot-on writing and quality acting – are also to be seen in this show.

It's a series of sketches about a diverse range of characters including enthusiastic Nordic Club Med reps, coke-fuelled fashionistas, Glasgow schemies and an over-hearty king, all performed with flawless accents. But while some of their sketches involve stock types, including the embarrassing dad's speech, or a bullying piano teacher, they are given an original and often unexpected twist.

Their sketch about a seedy lap-dancing club somewhere off a motorway junction, in which the lanky Stourton cavorts suggestively but hilariously as a bored and unhappy pole dancer, is both funny and wretched at the same time. It's one of a few sketches that have a hint of pathos and shows that Totally Tom have not just a sure touch with the funny and ridiculous, but a feeling for life's absurdities too. Until 28 August

Humphrey Ker, Pleasance Courtyard ***

Humphrey Ker is usually at Edinburgh with The Penny Dreadfuls, but this year the spoof Victorian theatre group have all been doing solo shows. Ker's is the most personal, as it was inspired by his grandfather's exploits during the Second World War, but there any connection with reality ends as Ker tells a very tall tale involving double agents, murderous mayhem and glorious incompetence.

So in Dymock Watson: Nazi Smasher!, Watson, all Brylcreemed hair and what-ho vowels, leaves his sweetheart behind in Blighty after he has been recruited by a terse Scottish spook and undergoes training by a comically homicidal Geordie. He's parachuted behind enemy lines in Romania, where he has to sabotage a Nazi operation, equipped with only a water bottle, a gun and a magician's outfit.

As fans of The Penny Dreadfuls might expect, Ker's script is full of puns, over-reached metaphors - “the silence in the room was thicker than an elephant kebab” - knowing asides and nicely anachronistic references. But while it is very well performed and the characters are nicely delineated, it's predictable pastiche and the joke wears thin long before the end. Until 29 August

Nick Helm, Pleasance Courtyard **

There has been a buzz about Nick Helm since he made his Fringe debut last year; lots of people have been citing him as the new Johnny Vegas, and certainly his high-octane, sweaty and sweary stage persona – I do hope it's a stage persona – with its mix of self-regard and vulnerability might put one in mind of him.

Helm's show, Dare to Dream, is a mix of one-liners, stories, song and poetry, in which this tortured soul, unlucky in love of course, goes from touching love poems to aggressive rants or loud, bombastic rock anthems addressed either to an individual in the front row, or the whole room. It's as if we are witnessing someone's breakdown, but the redemptive ending would put a lie to that.

The throughline is Helm's dream of writing the best Edinburgh show he can, and he starts off affairs with a “Good evening cocksuckers... and gentlemen” and a loud rendition of his song “Never Stop Dreaming”, with forced audience participation at the risk of being screamed at for non-compliance. There are two musicians on stage to provide accompaniment to the songs, sung in his increasingly gruff voice, who are there, it seems, merely to provide the pay-off to a gag about achieving one's dreams - however unambitious they are.

It's all a bit of a mess and the shame is that there's a talented performer trying to get out, as Helm's poetry and clever gags show he's a lovely writer - even if the good material is spread thinly through the hour. But this bad-boy shouty persona, played without any hint of subtlety, is just in-yer-face boorishness. Until 29 August

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