Beneath the swirl of noise, a droning army of generators provides a bass-line for the soundtrack of Lagos. The constant car engines fill out the lower register, while gangs of motorcycles, minibus taxis and trucks add texture to the sound above and below.
The horns from this sea of vehicles stuck in the morning traffic, or "go slow", are the punctuation in this heated urban conversation. A melody is offered by a thousand straining loudspeakers in a medley of Yoruba song, imported hip-hop and political Afrobeat. The choir is the beseeching street hawkers, the brimstone preachers and an occasional mosque muezzin. Above it all is a passing helicopter, whose deafening rotors act like an acoustic strobe. While some cities bustle, others buzz and some are said to even hum, Lagos roars.
Africa's biggest city, and by some estimates the fastest-growing metropolis in the world, is by turns intimidating and compelling.
To its political boosters, led by Lagos State Governor Babatunde Fashola, it is the "model megacity", a message he is expensively spreading in an international PR campaign that began this month. For intellectuals like the Dutch architect-philosopher Rem Koolhaas, Lagos offers a glimpse of how other cities will look in the future, places in a "constant state of becoming".
Most Westerners are simply terrified of it, believing they won't make it beyond the notorious Murtala Muhammed Airport. For the 6,000 newcomers thought to arrive every day from across the West Africa region, the city holds the promise of something more than surviving: the possibility of riches for people who have little or no choice. But few have any conception how hard that will be.
Megacities and their evolving shape have returned to the centre of the global conversation about how we live since the latest UN Habitat State of World Cities Report reminded us that the moment when the world's urban population will come to outnumber those living in rural areas is no longer a forecast but a fact. The UN experts focused this year on the immense "population corridors" that are forming around the world, merging already huge cities into unprecedented and unbroken urban landscapes.
Lagos is at the centre of both the poorest and likely fastest-growing example of this. It is the economic engine for an entire region that, unlike its Chinese or Brazilian megacity counterparts, is not lifting large numbers out of poverty but is concentrating ever more extreme wealth in the hands of a tiny minority. This phenomenon has been underlined in Mike Davis' dark vision in Planet of Slums, and in Koolhaas's tome, Lagos: How it Works.
In a city where most of the almost 20 million inhabitants live on the fringes, it would be hard to find a more marginal life than that found in Makoko. A floating slum that stretches out from land reclaimed from Lagos's lagoon by the accumulation of urban debris, the area is home to an unknown number of thousands. Among them is Joseph Blabi, a self-possessed 28-year-old who resents people calling it Makoko, a name which he says is reminiscent of the fishing village that it once was. He prefers "Mak-town", which he says sounds more "urban" and helps to break down the feeling that his home is somehow separate from the urban jungle beyond it.
Joseph has a definite style which fits perfectly with his vision of Mak-town. Of medium height, lean and muscular he wears tight jeans with an exaggerated wrinkle effect and a loudly patterned pink and red sleeveless shirt. The look is finished by a pair of jewel-encrusted sun-glasses with blush-coloured lenses.
When asked what he does for a living, the answer – as with almost anyone else you speak to in Lagos – has multiple parts. He's a dedicated churchgoer and volunteer with the Salvation Army, where he learnt to play the cornet; he's an up-and-coming actor in Nigeria's prolific film industry, Nollywood; and he's an occasional community host who likes to show guests the range of attractions in Lagos's answer to Venice.
His home, he explains, is best seen from one of the dug-out canoes that punt up and down the narrow waterways between its crowded shacks. He tells how according to local legend Makoko was created by the magical union of a local Yoruba carpenter and a visiting Egun fisherwoman from what is now Benin.
"She would bring him crabs and fish and shrimp, and eventually they fell in love," explains Joseph. "Their children became Makoko."
To understand what the place has become you need to move beyond the fringes of the claustrophobic slum, into the clear water where you reach a view of the horizon that is broken by a huge mobile-phone transmitter disguised as a fake palm tree. Lowering your eyes you meet the glistening convoys of 4x4s that, with blazing lights and sirens, speed along the expressways. Great spurs of road that connect the lagoon's islands and the mainland, they were built on concrete stilts in the Seventies and Eighties.
Beneath the expressway hangs a cloud of smoke that rises above the rusted tin roofs of Makoko – wooden shacks built on their own stilts, where bars, brothels and hair salons compete for space with fish-smoking operations, hostels, net repairers and much more.
In the watery lanes between the shacks, floating shops make their way with phonecards, sweets, biscuits and tea. Fed by an endless supply of raw sewerage, which falls from hundreds of crude outhouses at eye level as you pass, the water itself is so dark and viscous that it seems to part only reluctantly on either side of the hull.
Naked children splash about in the toxic water, jumping from one dug-out canoe to another, or swimming from one shack to another. Underneath the huts, in the grey mounds of plastic waste that form dykes of rubbish, chickens peck away in search of something nutritious. Just above the waterline thousands of what look like armoured white lice swarm over the wooden supports, making use of the final inches of available space. "Those coming here are those who just hear about Lagos," says Joseph perched dead in the middle of the canoe, not wanting to touch anything.
"They have no idea how hard it is to survive here." There is nothing close self-pity in his voice, nor is there hopelessness. "Lagos is good; it's not bad," he insists. "Yes, you have to work and struggle. It's only good for those with business IQ," he says, leaving no doubt that that includes him. "Lagos isn't a place where come and sit down. You come to work. It's not for the lazy and it's not for the old."
By now back at home, the young actor's analysis is interrupted by the arrival of the "chairman".
Like much of the megacity, Mak-Town is usually beyond the reach of the conventional authorities, and in their absence the notorious "area boys" offer their own form of policing. It is part neighbourhood watch, part protection racket. Outsiders visiting Makoko are expected to offer some tribute to the area boys, and their "chairman" has come to collect. The area boys are effectively gangs recruited from the legions of unemployed young men who contest parts of the city, controlling everything from parking to drugs. They are also muscle for hire, and tend to make the most money during Nigeria's election seasons when politicians pay them retainers to make sure that people vote for the right candidate.
Spreading himself liberally over a ruined armchair, the "chairman", Zabi, is relaxed enough to admit that he runs a gang more than 50 boys. "It's not because I'm very strong," he's quick to point out, despite being one of the most feared people in Mak-Town. "It's because I'm organised. When I talk they listen."
At first sight, Makoko ought to be a world apart, a reserve for anyone willing or able to live here; but it's not.
On its land side, Mak-Town is under siege from developers who are looking to cash in on the growing desire of the wealthy to live by the water's edge. With no legal status and no government protection, the slum's residents are finding that even this precarious foothold in the city can be taken away from them to make way for modern estate houses surrounded by high walls topped with razor wire.
This is a development that has helped to enrich Zabi just as it ultimately reveals the precariousness of his survival. He explains that the developers came to negotiate protection when they moved into the area, giving money to the area boys under the guise of hiring security.
They target the majority of homes which don't have official documentation, giving people six months to move before demolition. The area boys, he says, are the ones sent in to get people to leave.
The chairman is philosophical about what will happen if and when it's his own house that's slated for demolition. "If it happens, there's nothing I can do. After all, better people than me have been sent away," he says with a smile. "Even if I stand and fight, I will die alone. Who am I to question the rich people? Who am I to fight them, even if they're not right?"
His answer in some ways encapsulates the curious mixture of ambition and hustle that epitomises Lagos, but comes with an acceptance of the glaring inequality of the place. The point, as Joseph explains, is not to bring the wealthy to heel but to "get rich".
Despite the infinitesimal chance of that happening, people still come. The new arrivals even get their own acronym, a game that Lagosians are exceptionally good at.
Abina is a "JJC" a "Johnny Just Come". He looks no older than 10 but insists that he is 15. He came to Lagos to find his brother and in the process has found work hawking plastic name-badge holders and wallets for 14 hours a day. His tiny body is swaddled in the strings on which his products hang, giving him the appearance of a small, multicoloured mummy.
"I didn't want to come to Lagos," he says shyly. "But there was no school in our village." His brother has put him to work, he says, with the promise that if he does this for another 18 months he will be allowed to go to school. He doesn't like the work and is frightened of the city centre, but "nothing is for free".
Like many JJCs, Abina's work place is the chaos of Lagos Island, at the other end of the Third Mainland Bridge from Makoko. It's a place where anything and everything can be bought and sold. A quick survey of goods balanced on the heads of passing hawkers shows roasted almonds, spare parts for watches, boiled eggs, plastic sacks, mangos, body parts from mannequins, the usual CDs and DVDs, razor blades, inner tubes for bicycles, and packets of "Adam's Desire"(a remedy for "problems with performance"). One lady shelters from the blinding sun with the help of an umbrella fringed with phone cards.
The book stalls that spill out from the bus station corner opposite the old Anglican Cathedral stalls offer their own window into the city's modus operandi: think big. One tattered volume that stands out is The Book of Successful Swimming Pools. Other titles, alongside the obligatory Audacity of Hope by one Barack Obama, include: Young and Rich, Manage Your Time, The Power of Your Destiny and Turning a Business Around. In fact there are only really two kinds of books among the stacks: religious or materialist self-help volumes.
A passing yellow and black mini-bus, of the type known as Danfos, captures the spirit with a slogan on its broken back window: "Upwards, Forwards Ever", it demands.
Thomas, an imposing man with a stars-and-stripes cap who can't resist stopping to ask if there's something he can assist with, is a classic example of the Lagosian refusal to be pinned down to a single identity and thereby risk missing out on a chance.
Asked what he does for a living, he replies thoughtfully, but without missing a beat, that he is an "opportunity businessman". This gloriously ambiguous career would be claimed by hundreds of thousands of the megacity's hustlers. It's part of the reason why wherever you look in an often scorched and bleak urban landscape there are signs warning the onlooker that "this land is not for sale". Long before the rest of the world learned about Nigerian fraud through the email scams, or "419s", Thomas's colleagues in the opportunity business were selling plots that didn't belong to them, to anyone foolish enough to buy.
The one relatively empty space in the teeming city can be found in the car park of the Power Holding Company of Nigeria. It gives the lie to Lagos's pretensions to be a "model megacity", as the concrete forecourt is littered with the evidence of chronic under-investment and statal collapse. Rusted black Peugeots with wheels missing and doors hanging off have been permanently parked in the shadow of the power corporation building, the facade of which has been scorched from the third floor up after an electrical fire. That irony will not have been lost on the millions who sit through maddening and constant power cuts. The wrecked cars have the letters NEPA painted on their sides. That was the old name for the power company that used to be known popularly as "Never Ever Power Anytime". It has since been rebranded to Power Holding Company of Nigeria (PLC) which was quickly changed to "Problem Has Changed Name (Please Light Candle)".
A popular pastime in the rich neighbourhood of Ikoyi Island is to sit in the waterside bars and watch the alternating light and dark as power is switched up and down the lagoon shore from one neighbourhood to another.
The seriously wealthy, or helicopter class, sometimes call the switching station and get them to leave the lights on in their district if they're hosting a party that night.
That is not an option at Joseph's two-room shack in Mak-Town. And he starts to sweat heavily when the power goes off as he plays "Abide With Me" on his Salvation Army cornet.
Two little sisters crowd into the tiny front room and another friend comes to listen to the wavering notes. Joseph admits to getting down some times and feeling the pressure of being the "local celebrity", with people always coming to him for money. His biggest role so far was as a corrupt pastor, for which he netted £40. It's tough to get parts if you don't have the connections, he complains.
One thing he's sure of is that he will make it. There's no room for doubt. "I want to act in a big epic," he says pointing to a bootlegged DVD containing all of Chuck Norris's Missing in Action franchise.
"Of course I will be successful. And when I'm rich I'm going to build a really big house out on the water," he says echoing exactly the ambitions of those who want his Mak-Town demolished.
600,000/year - rate of population growth
20,000/square kilometre - average population density
40 degrees centrigrade - maximum temperature recorded in May
1 per cent - proportion of households that has reported the murder of a family member
17 million - estimated population
$28bn (£18bn) - estimated Gross Domestic Product
6,000 tonnes/day - amount of solid waste generated
68 per cent - proportion of Lagos residents classifying themselves as Christian
300 square kilometres - Lagos metropolitan area
$1,036/year (£670/year) - average earnings per inhabitant
All figures refer to Lagos metropolitan area