It could have been an embarrassment all round; a bunch of blokes in their seventies revisiting material that was anarchic and transformative 40 years ago but which they are now performing for 10 lucrative nights in the home of commercial comedy. Fear not, though, Monty Python Live (almost): One Down Five to Go – surely the final farewell tour – proves that quality endures. And in the hands of the show's deviser and director, Eric Idle, it can be made into something new and fresh as well.

A move from E4, where sketch duo Cardinal Burns's debut series was shown, to Channel 4 is a significant jump. A bigger budget (one presumes), a broader target demographic and the confidence of your employers should act as a fillip to performers; on the evidence of last night's opener to their second series, that confidence was well placed.

A couple of weeks ago I was queueing to get into the BBC’s magnificently revamped HQ at Broadcasting House. Just behind me in the same queue were Harry Enfield and Paul Whitehouse. Their faces are craggier, their hair less confident than when the two comedians became part of the national furniture 20 years ago. And here they were, lightly joshing about the indignity of signing in to enter the offices of the national broadcaster which owes them so much.

It’s a truism of the impersonator’s art that those who can do other voices have none of their own. On Parkinson, Peter Sellers couldn’t even come down the staircase as himself. When at the end of the show Mike Yarwood said, “And this is me!” a nation switched off. The idea behind The Mimic, starring the remarkable Terry Mynott, is that it accepts the truism as truth. This is a comedy about a man who can pose convincingly as Ronnie Corbett stuck in a postbox but has no life to call his own.

Lorna Watson and Ingrid Oliver, purely by dint of being female, have a burden of expectation before they even open their mouths, as the ghosts of French and Saunders stalk the corridors of the BBC. It's horribly unfair to saddle the newcomers with that burden of course, but, given the dearth of female comics on television, it's perhaps inevitable. Yet the fact that the corporation thinks highly enough of Watson and Oliver to launch them straight on to BBC Two, rather than the safer comedy testing ground of BBC Three, makes a big statement in itself.

Andrew Maxwell, Assembly ****

Thank goodness for a performer like Andrew Maxwell. The Edinburgh Fringe opens just as parts of the UK take a mad pill and start shopping outside normal opening hours. Most comics ignore the mayhem, while some insert a clever line or two, but Maxwell ditches his opening 15 minutes and writes completely fresh material about the state of Britain today in the light of the riots in England.

Thank goodness for a performer like Andrew Maxwell. The Edinburgh Fringe opens just as parts of the UK take a mad pill and start shopping outside normal opening hours. Most comics ignore the mayhem, while some insert a clever line or two, but Maxwell ditches his opening 15 minutes and writes completely fresh material about the state of Britain today in the light of the riots in England.

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.

Kieran and the Joes, The Store ****

Kieran and the Joes are a three-man sketch group (Kieran Hodgson, Joe Markham and Joe Parham, working with co-writer Tom Meltzer) who are young, personable and very neatly dressed in shirts and ties - but while they may appear clean-cut their comedy veers nicely towards the dark.

Adam Riches, Pleasance Courtyard ****

From the moment Adam Riches bursts onto the stage, spewing his business cards around as a manic showbiz agent who wants to sign up everyone and everything - including even the venue's walls and floor - this is a show of hyper energy and absurdist comedy.

Tiffany Stevenson ★★★★

The comic is currently appearing on Show Me the Funny on ITV, where her smily disposition is a welcome antidote to some of the sneery critics they have mustered. There’s boyfriend stuff in Cavewoman but Stevenson also delivers a few astute political observations, as well as the occasional unPC gag - such as suggesting Tina Turner's dance moves were inspired by her avoiding Ike’s punches.