Risking a red face for the sake of a red nose

The current trend in television documentaries is to leaven heavy material by pairing it with a light entertainer. Thus Clive Anderson is sent to overdeveloped holiday spots, Griff Rhys Jones is prescribed as an emollient for the painful business of reading, and sundry Pythons go off on pet crusades of their choice.

The whole thing started with Comic Relief, a venture in which funny people tease the money out of your pocket and into African aid projects with punchlines. Although in this case the game is very much worth the candle, the idea that your modern British viewer can only be improved through laughter is troubling. The idea of the charity event, in which the money you pay to have a good time alleviates a social problem somewhere beyond your ken, has been around for a while. But unlike a royal gala or a stadium rock concert, Comic Relief and sundry other fundraising regulars on the box make the link between entertainment and education: they are mutually dependent; they are each other. It's an alliance that can only be brokered with the help of rare communication skills.

Even in the title of Billy Connolly's Return to Nose and Beak (BBC1), so-called after the misnomer the comedian's daughter applied to Mozambique, the jocularity feels ever so slightly forced. But Connolly, doing a little routine about the absurdity that is compassion fatigue, or standing well back from the land-mine disposal team, possesses those skills. Despite a barrier of language, culture, colour and wealth, his rapport with orphans and urchins and large crowds of disenfranchised children seemed genuine and unpatronising.

In advance of the fifth Comic Relief day, this documentary took Connolly back to the country from which he reported in 1989. With the civil war over, the improvement in social conditions has been marked. Deaf children are learning sign language, mines are being cleared from fertile agricultural land, and children and parents separated by war are being reunited. One of the war victims encountered in the previous visit has clearly not allowed the loss of her legs, blown up when she stepped on a land-mine, to hold her back: since then she's had as many sets of prosthetic appendages as she's had children - three of each.

Although films like this cannot be made without a degree of planning, one of its charms is that things don't run too smoothly. True, one magnificent shot of an old steam engine, thrusting through the abundant bush along a line obscured entirely by thick undergrowth, looked like a refugee from a slick travel documentary, but overall there was no disguising the nuts and bolts. The hunt for a boy who, six years before had graphically described the slicing up of his parents, genuinely appeared to take several hours: by showing how difficult it was to find him, the programme astutely brought home the boy's plight as a street vagrant.

At one point, in order to explain what a cumbersome business the gifting of aid can be, Connolly swung the camera round on to the huge operation of which he was just the tiny, visible part. But no amount of pre-emptive apology could dissolve the thorough discomfort felt from watching the last stretch of the programme. Here, Connolly accompanied a man to a village in the bush, where his two long-lost children had been located. As he and his daughter howled and wailed, and his unremembering son stood stiffly alongside, not knowing where to put himself, the presence of a Scottish comedian and his technical entourage could not have looked more intrusive or unwanted.

The case for the prosecution is that privacy should not be sacrificed on the altar of publicity. The case for the defence is that it's all in a good cause, that breaking in on one such reunion will raise enough money to fund 10 more. Which, on balance, means that the case is dismissed.