Enjoyable and amusing end to the season, as some long-running plotlines are resolved. Ruth Madoc, star of 80s holiday camp sitcom Hi-de-Hi!, continues her second career as a camp icon as she makes a guest appearance as Glynn's wife Rhiannon, relieved their "wife swap" holiday is at an end. Clive's luck doesn't seem to be getting any better when he invests unwisely in Spanish property - happily he, Tiger and Terri come up with a plan to get his money back. It's not all good news: Mateo's mother-in-law wants to kill him.

Tonight's second episode of this circus-set sitcom relies on old-fashioned shtick such as a clown catching fire and delusional Georgie (Ruth Madoc) believing she's being bossed around by her performing dog. It's gently amusing, old-fashioned comedy, with the bonus of Amanda Holden in short shorts.

The setting - a small-scale circus - is colourful and original. The characters are fun. The cast, which includes Tony Robinson, Sophie Thompson, Ruth Madoc and John Thomson, is comprised of rock solid comedy pros who deliver the goods. It contains gently romantic elements which are rather sweet...

Truth be told though, I didn't find it funny. With one or two exceptions, the gags are limp and lumbered with punchlines Nostradamus probably saw coming. Moreover, it has as its star Amanda Holden, who totally fails to deliver any kind of performance through the mask that is her face.

The Hi-de-Hi! fan in me wanted to like Big Top (BBC1), the unashamedly 70s-style sitcom with Amanda Holden and Ruth Madoc and John Thomson, but it was just unashamedly lame. Surely if you have a circus comedy, the challenge is to create the world's first funny clown? Would putting ferrets down his trousers help? No it wouldn't. I couldn't believe Tony Robinson (Erasmus, the odd-job man) spent all those years of training on Blackadder and those archaeology programmes for this.

Do we really have to speak about Big Top? OK. Big Top is a sitcom about a failing circus, inexplicably starring the wooden, joke-killing Amanda Holden as the scatty, though apparently strong-willed, owner. There's a trapeze artist madly in love with her, Ruth Madoc as a dog-handler, and other rather good actors (Sophie Thompson, John Thomson) flailing with a lame script. Patrick Baladi as a health and safety advisor was ejected at the end of episode one after failing to persuade Holden of the merits of a life of mortgage trackers and convention. Lucky him. Poor us.

Big Top, a new sitcom set in a travelling circus, is one of those programmes that get you wondering about the commissioning process. You'll need something to entertain you while it's on and speculating about the way it came into being will do as well as anything, unless you've got a dog that's overdue for a combing or some socks to pair up. One assumes that the performers' names came first on the pitch document. One certainly hopes that they came first on the pitch document, since the idea that it was sold on the essential concept and a sample of the writing seems implausible, to say the least. We've thought of a vehicle for Amanda Holden, somebody said, and what's more it's a role that will make it feasible for her to wear hotpants and black stockings nearly all the time. And if you bite there's a good chance that we can bolt on John Thompson, Tony Robinson and Ruth Madoc. How's that for belt-and-braces coverage? Cold Feet, Blackadder and a dab of Hi-De-Hi! behind the ears.

"So what's the sit?" asks the commissioning editor. Down-at-heel circus, replies the pitcher, run by Lizzie, a mildly over-controlling ringmistress who's the only grown-up on payroll. There's a terrible husband-and-wife clown act, a depressive East European acrobat with a crush on Holden's character, a cynical soundman called Erasmus (Tony Robinson) and the self-seeking Welsh dame who does a performing-dog routine. Oh, and it's written by Daniel Peak, who wrote Not Going Out, so there's a bit of pedigree there. Lot of running gags, lot of slapstick, comedy of types. Think Dad's Army with red noses and spandex tights. And then, one guesses - since it's not very often these days that sitcoms get green-lit without jumping through this particular hoop - there would have been a rehearsed reading of the script, so that a collection of executives could mull over its prospects. And it's at this point that speculation hits an obstacle. How could they sit in the presence of gags this lame and character depiction this arbitrary and not say no?

It does go out at 7.30pm, so it's possible that the younger audience will be advanced as an alibi. It seems heartless to use children as a human shield in this way though, and surely they deserve better than gags about ferrets down trousers and punch lines that audibly creak as they're winched into place. "I was so worried that you'd fail us on the raw sewage round the hot-dog stand," blurted out Lizzie when the health and safety inspector gave her the all clear, a line that not even Helen Mirren could have made psychologically plausible. And without an underlying psychological plausibility (the urgent cartoon drives that you'll always find in Hi-De-Hi! and Dad's Army if you dig deep enough) it just isn't comic. That line isn't an inadvertent revelation - it's hopelessly, mechanically advertant, only there to be funny. In the end, an exchange between Plonky the clown and Erasmus offered the best verdict: "If we're so terrible why do we get a big cheer when we finish?" "I think you've answered your own question there."

Suddenly it's like the 1970s all over again, at least in TV sitcom land. If it's not Miranda gurning to camera and tripping over her giant feet, then it's Amanda Holden in fishnet tights and John Thomson shoving ferrets down his trousers. Which, sadly, is not a scene from a retro fetish club night but what passes for comedy on the fantastically rubbish Big Top.

The Office must have seemed another lifetime to Patrick Baladi when he found himself stranded amid the spit and sawdust as a health and safety officer in a circus sitcom so old-school it made Last Of The Summer Wine look raw and edgy. Assigned to the unenviable task of romancing Holden's dull ring mistress - think school ma'am on a hen night - Baladi was confronted by a box of dog poo. No, seriously, that was the punch line of the best joke of the night.

It was the once mighty Gladys of Hi-de-hi (aka Ruth Madoc) who was proffering the said turd, which made you feel for the talent being frittered away all round the ring. Sophie Thompson is a talented comic actress, but she has an unhappy knack of ending up in total turkeys and she's picked another one here as Thomson's clueless co-clown.

It was as though The League of Gentlemen had never happened. You can squeeze laughs out of clowns without resorting to abusing furry animals - the consistently excellent Modern Family had a great running gag about coulrophobia last week - but Big Top isn't anywhere near that league. The title isn't even a joke: it might have worked if Jordan was playing the lead but as it is it's just plain lazy. Another tent-peg in the coffin of the British sitcom (it's got so bad, I've even started laughing at Miranda. But that's probably the medication).

Reports of the death of the British sitcom have been greatly exaggerated. With Last of the Summer Wine making its 31st series, My Family its 11th and even Reggie Perrin recommissioned, somebody's watching. And they're the same viewers likely to warm to this new family-friendly sitcom set in a two-bit provincial circus.

It stars Amanda Holden as ringmaster Lizzie, who struggles to control a gaggle of fading acts, including a wacky ageing performer (Hi-De-Hi!'s Ruth Madoc) and a pair of hopeless clowns (John Thomson and Sophie Thompson). The script by relative newcomer Daniel Peak features dog-napping plots and ferrets-down-trousers gags rather than the observational humour that's so hip these days, but it draws upon the rich tradition of earlier comedies - from Dad's Army to Steptoe and Son - in which the humour often came from characters who are compelled by their situation to do peculiar, funny things. Spirited performances by a decent cast go some way toward making up for the dated set-up. Baldrick himself, Blackadder's Tony Robinson, turns up as the circus's wisecracking accounts man, and Holden propels the action (she was, after all, a perky comic actress in Kiss Me Kate and The Grimleys before Britain's Got Talent and Botox took over). Launching any new sitcom is a bit of a highwire act, but audiences may roll up to this one.

You won't have seen many adverts for Amanda Holden's Big Top, BBC1, 7.30pm, because the BBC are embarrassed about it. Correctly. It's worse than it sounds. That's worse than a sitcom featuring Amanda, Tony Robinson and Ruth Madoc in a circus sounds. Think on that.

With Britney Spears and Take That going down the circus route for their recent albums, suddenly the big top's back in vogue. But even if it didn't feature Ruth Madoc as one half of a dog act (the other half being a West Highland terrier called Dave) the ghost of Hi-de-Hi! hovers over this show.

Like holiday camps, a circus - where this is set - is like a sheltered environment where all kinds of eccentrics can live in safety, at arms' length from the outside world. The genial folk at Maestros appear to have been preserved in aspic from some time in the 60s and their biggest star seems to be Amanda Holden in a ringmaster's outfit.

Also on the bill are Tony Robinson as a grumpy caretaker named Erasmus, leotard-wearing Boyco, (Bruce MacKinnon) and John Thomson and Sophie Thompson (not related) as a pair of clowns, Jeff and Helen.

The gentle comedy tonight revolves around some ferrets down a clown's trousers and a visit from a health and safety officer - who's played by a seriously bemused-looking Patrick Baladi.