Welcome, then, to Lagos, which to European eyes can look a little like something imagined by Hieronymus Bosch. Please make yourself at home - assuming, that is, you can find a spare inch on which to plonk your bum, for this is a mega-city, its population somewhere approaching 16 million, a figure that increases by 600,000 every 12 months.
Now, I'm not at my best in traffic and crowds and, though I love London, another mega-city, I'd be lying if I said that it doesn't get me down. There are times just lately - some thug is playing his car stereo chest-thumpingly loud, and I'm stuck behind him in a mile-long jam - when I've felt like Michael Douglas in Falling Down. So was I looking forward to the BBC's new series about Nigeria's former capital? Er, no, I wasn't. Cars, pollution, shacks, burning tyres, corruption, poverty. Just watching the trailer made me feel all hot and scratchy.
Ten minutes in, though, and I understood that Welcome to Lagos (BBC2) is great: one of the most moving, interesting and (this is the weird part) uplifting things I have seen in years. If David Cameron really wants to teach young people life lessons - I refer to his volunteer army, or whatever it's called - he should just send every 14-year-old in the country a DVD of this series. Chastening doesn't even begin to describe it. Joseph and Eric, the stars of part one, work on a huge dump where they pull rubbish from its stinking mountains, which they then sell on. It is a horrible place, rank and dangerous, and their work is relentless and badly paid. Yet they embrace it, seeing it not as a vision of hell, but as some great and benign gift: an opportunity.
What is life on the dump like? "Hard, very hard," said Eric, a wannabe rap star, but he was grinning as he spoke, thinking, perhaps, of his wallet, snug with fresh notes. Joseph, a family man, said he would gladly go to an even stinkier dump if the money was better. He said the word "stinkier" with an exuberance he might otherwise have reserved for church.
Dickensian is an overused word, but the creator of Sam Weller and Mr Micawber, of Fezziwig and of Joe Gargery, would have loved these men, their sentences by turns funny and sly, poetic and heartfelt. Impossible not to cherish the biblical cadences of their speech. Eric tucked in to a plate of fried cow skin cooked for him at one of the dump's rudimentary restaurants. "I wouldn't say this is the best food in Lagos," he told us, solemnly. "But it's the best food in the dump." Later, confessing that his friends in the music industry were unaware that he was a scavenger, he said: "I'm working so hard, and I know that sooner or later God will put a smile on my face and my soul will become joy." (Notice his use of "and" not "but" to join the two halves of this sentence together.)
Leaving the dump, we headed for the meat market. No cling film and chill cabinets here. Across the screen came a wheelbarrow full of hooves and a vast plate - it wobbled on a woman's head - loaded with cows' heads. Both were merrily picking their way through intestines, which lay everywhere, like giant ropes of frogspawn. Gabriel's living was turning animal blood into fertiliser, not an easy job, because it involves such heat (the blood must be cooked until as black as pitch). "It tortures you," he said. "But I like a hard job. That's my policy."
This is beautiful, replete television. It tells you a story, with characters and an old-fashioned plot; it opens your eyes (and ears) to a place you're never likely to visit; it reminds you to count your blessings even as you remember that it is far too easy to patronise the poor of the developing world. And it does all these things without ever being didactic, politically correct or manipulative. It is, to sum up, a minor miracle - and in consequence, it leaves me feeling more worried than ever about what a new government might do to the institution that was visionary enough to make it.