David Chater

In Trevor Griffiths's masterpiece The Comedians an elderly comedian teaches an evening class for aspiring stand-up comics. He makes them close their eyes and think of any personal experience that has affected them deeply. Right, he says. Open your eyes. Tell us what you were thinking - only be funny about it. Contained in that one exercise is the acid test of comedy, and it explains why Jam & Jerusalem has improved out of all recognition. Rather than going for easy laughs, it focuses in large part on the relationships between Sue Johnston's character, the new friend in her life and her two semi-grown-up children. In a gentle Sunday-night way, it is truthful and funny.

Animals are anarchists, and here is a wealth of tremendous footage showing them doing all manner of things that they shouldn't. Ostriches, squirrels, badgers, ferrets, pigs and snakes attack presenters as if they hadn't eaten for years. Expletives are bleeped, blood flows and cameramen fall about laughing. Po-faced commentators try to do pieces to camera while cows hump joyfully in the background. The programme doesn't amount to much and Clive Anderson's banter is painfully laboured ("John Noakes famously ended up with smelly brown muck all over his shoes. Some say he was nervous and badly trained, but I'm pretty sure it was the elephant.") But you can't beat an animal behaving badly.

Even if the comedy here was always too broad to cut it with the best of satire, the series ends very much as it began - with a gentle burbling of in-jokes and good humour. The BBC's senior foreign correspondent has begun to suffer from such chronic sexual frustration that he is displaying symptoms of dementia. In desperation he rings up Jennie Bond - playing herself - in the hope that they could "do things" together. "I've said it to John Humphrys," she replies, "and I say it to you. NO!" This final episode also represents the triumph of the underdog, as Harry the hapless stringer (Bruce Mackinnon) finally shows a glimmer of talent. At the very least, this was a better class of light entertainment.

Previewers were asked specifically not to reveal the ending of this bizarre and wonderful series. Fair enough - although the ending is so strange that not many previewers would be able to give it away even if they wanted to. Under the circumstances, I'm hanging on desperately to what little I know. There is an outrageously funny scene tonight when the serial killer tries to confess his crimes at a Haringey police station, which was very similar to my own experience a few years back when I tried to hand in a wallet at Wood Green police station. The programme goes on to provide invaluable advice on how to cure Paradise Syndrome, which can afflict anyone who suddenly finds himself with everything he ever wanted. As for the rest - well, heaven only knows what was going on. But it was imaginative and brilliantly acted, and I loved every sick and confusing moment.

It's the penultimate episode of a series that shows no signs of returning to Planet Normal any time soon. All the characters are worried that their mysterious blackmailer is "deeply disturbed" and "bordering on the psychotic", which brings to mind pots and kettles of the blackest variety. As the story unfolds, they are all drawn to a disused hospital in readiness for a macabre showdown. But before that can happen, the Mother & Son team of serial killers (Reece Shearsmith and Steve Pemberton) are preparing to dispatch one final victim. Mum wants to buy an indoor barbecue in readiness for the occasion. "I thought we could do something special," she says, "and eat her. What do you think? I've bought some red onions." "That's disgusting," her son replies. "I don't like red onions."

This, sadly, is the final episode of Jo Brand & Co's superlative series. Because it is based on mood, inflection and myriad flashes of acute observation, Getting On is almost as difficult to describe as a piece of music. Certainly there are headline events in each episode - tonight, for example, there is a "conflict resolution strategy meeting" and an argument about who won the raffle - but it's the interaction of the characters around these events that is so accurate and funny and wonderful. It is bound to be recommissioned; nobody would be mad enough to let something this good slip through the cracks. When that happens, I hope they continue to go for accuracy rather than leaning towards laughter, because it was the truthfulness that made it so extraordinary.

The quality of the stand-up comedians in the series has been so high that it isn't a question of one being better than another - it just boils down to which one you happen to like the most. My personal favourite tonight was Jon Richardson, mocking his own nerdy appearance and funny voice. "This is not a voice that will accentuate a sexual experience," he squeaks. Jo Caulfield discusses her mates ("Every woman has a slutty friend. And if you can't think who it is, it's you"); Micky Flanagan recalls the academic shortcomings of his East End comprehensive ("No kid from this school has ever gone on to drive a van"); and Al Murray's pub landlord explains the existence of God.

Of all the episodes in this strange series, this is the strangest and most fascinating to date. It is a homage to Alfred Hitchock's 1948 film Rope with James Stewart, which told the story of two young men who murdered a classmate, put his body in a wooden chest and invited the victim's friends and family round to dinner. It was a daring and experimental film, shot as though it were taking place in real time using long, unbroken takes. The same technique is used here, with a single location and only three characters - the comic killers (Reece Shearsmith and Steve Pemberton) and their unfortunate victim (Mark Gatiss) - shot in two long takes. The effect is theatrical, claustrophobic and totally mesmerising. One of the greatest pleasures of watching television is coming across a complete surprise; in the fast-forward world of snappy editing, tonight's episode has a shocking originality.

This is followed by Jo Brand's superb new comedy, Getting On. Set in the geriatric ward of an NHS hospital, it is centred around four brilliantly observed members of staff - a nurse newly returned to the NHS (Jo Brand), a subtly insane nursing sister (Joanna Scanlan), a male matron (Ricky Grover) and a brittle doctor (Vicki Pepperdine). Directed by Peter Capaldi, it is filmed in the verité style of The Office and The Thick of It using shaky cameras and dialogue that sounds overheard rather than scripted. It was the wonderful surprise of the week.

There must have been a lot of wicked fun in the making of this series, which does for foreign correspondents what Drop the Dead Donkey did for a television newsroom. A senior foreign correspondent (Martin Jarvis) and his crew arrive in Africa to cover the outbreak of war. But the fighting is nowhere near as fierce as the rivalry between this grand old man of journalism, a young local stringer who resents having his thunder stolen, and a battered BBC World Service correspondent. Although much of the comedy is broad, it could have been written only by an insider and much of the jollity comes from sharing an in-joke. One of the writers was Tira Shubart, a producer and journalist who lived with John Simpson for ten years.