They call themselves a gang, but they seem barely men. Their name is taken from the estate around us, dark stairwells and closed doors just visible under a railway arch. We are close to Cable Street, the famous East London road once known for its sailors and brothels, and where Oswald Moseley's fascist party tried to march in the 1930s.

The Martineau Boys have a reputation. Near-decapitations and shootings have been reported as estates holding menfolk and cousins from villages back in rural Bangladesh have gone to war. "You're a copper, innit?" says one blue-hooded youth. He sucks in through his teeth. The rapper 50 Cent booms on in the background. "Yeah...Mr Undercover Cop," he repeats. The others eye me with suspicion. "You got a wire, Fed?" They seem convinced that a van parked nearby is an unmarked police vehicle – mine.

There is the sound of breaking glass as a taillight is put in. The smell of marijuana is strong. Eyes shine in the glow of reefers. A car screeches around a corner, two Bangladeshi men in front, three white girls in the back. Good-natured insults are traded in 'Banglish' (a mix of English and Bengali) with the kids on the street. A door opens somewhere and a stream of young men, about 30 strong, floods out, all baseball caps and slicked hair. It is 9pm and Friday night is just warming up.

This is Europe's most powerful metropolis. Barely a couple of miles away the City glitters. Canary Wharf beckons from its needle-like point. Yet down here, here in “the Abyss” as the American author Jack London once called it, life can be dictated by the street. Unemployment and overcrowding among the predominantly Bangladeshi population is high, drugs (particularly heroin) and prostitution evident. Gangs have taken hold on the crowded estates, different crews "beefin" [fighting] or "kotchin" [hanging out] on corners near the ubiquitous PFCs (Perfect Fried Chicken). Everyone seems somehow related, through extended family and village networks that have travelled over from Sylhet in northern Bangladesh. It is a tight, closed world which – just occasionally – feels a little like the streets of West Baltimore in cult US TV series, The Wire.

Yet the 2012 Olympics are on the horizon. The cranes are already at work. The edges of east London are changing as they prepare to welcome the world. Slowly, but surely, new wealth is transforming one of history’s most famous ghettos: The East End.

Today Robert De Niro and Cher have apartments in the gentrified and redeveloped Docklands. Gilbert & George, Tracey Emin, Rachel Whiteread, disgraced Boy George and other artists have flocked to Brick Lane. Forty-plus nightclubs also line the once-forbidding alleys and sidestreets of Shoreditch, where Fagin and Bill Sikes plotted their awful deeds in Charles Dickens' Oliver Twist. The old Jago – a twisting Victorian ghetto in which police feared to tread – is now Banglatown, named after its Bangladeshi hosts, whilst nearby Spitalfields market is swallowed in redevelopment.

Long home to immigrants, 100 years ago the East End was the centre of the Jewish community in England. Now the azan, the Islamic call to prayer, sounds out from Whitechapel's towering East London Mosque. It beckons the gangsters and Bengali “shottas” [dealers] following the paths of the Kray Twins and others down through history before them. You can see it on the streets, in the Saudi garb and beards outside the massive London Muslim Centre. Because the gang-christened “Endz” are now turning to Allah.

Respect

They called him the Flour Man. We are standing at Arnold Circus, a famous roundabout just off the end of Bethnal Green road and close to the headquarters of George Galloway's Respect movement, which has taken much of this area by storm. Youths constantly criss-cross the area on their bikes. An innocent enough scene … except that some are probably “workers”, the bottom of the pile in the drugs scene, shotting wraps of “white”, “brown” and “rocks”. Occasionally a Merc or Lexus cruises up, a quick call taken on a 'business' (drugs) line, before moving off.

"I used to rent a flat here," he says, hands in his pockets, a figure lost beneath the looming Edwardian tower blocks. "Some crazy times, bruv. We used to rip off other dealers. I was cuttin' my drugs with flour and that's how I got my name."

Rasul Miah, 28, stands, reflecting, for a moment. Short and stocky, he is dressed in loose-fitting jogging trousers, a sweatshirt, open-toed sandals and sports a full beard. His thick Cockney accent runs over a mix of English, Syhletti and Arabic. His phone rings with a sonorous Arabic chime as he takes constant calls from "the brothers".

When we first met, some five years ago now, he was barely a month out of prison. He'd done a four year stretch for conspiracy to supply Class A drugs. In the Scrubs he'd found God – Allah – and taken the shahadah [conversion ritual]. Ashhadu Alla Ilaha Illa Allah Wa Ashhadu Anna Muhammad Rasulu Allah is what you repeat. “There is no god but God, and Muhammad is his Messenger ...”

There are a surprising number of men like him, culturally Islamic but not practising Muslims who "revert" whilst inside. For some, it's simply a means to some extra concessions. For others, like Rasul, it has become a way of life: it literally shapes their every waking moment.

I had met Rasul via his friend Sajid, a stern-faced, charismatic Bengali with his own cable TV show. A former gang member, he was studying to be a lawyer and was a main figure in the Young Muslim Organisation (YMO) and Islamic Forum Europe (IFE), politically-active Islamic movements based out of the nearby East London Mosque. Best-selling 'The Islamist' author, Ed Hussain, who grew up around here, argues these are radical networks linked to groups in Asia such as Jamaat-e-Islami, which want to establish sharia law and an Islamic caliphate. The organisations themselves deny this, pointing to their work on police boards, local schools, in youth projects, in inter-faith forums and supporting efforts to prevent extremism. Young men like Rasul are now their footsoldiers: men of God, not crack cocaine.

Rasul had once made his living running street soldiers, though, paying them regular wages, ripping off other dealers and organising protection rackets. Drugs brought him wealth, but also sorrow. “You can't relax, you get paranoid, always expecting the rip-off, or police, or other problems," he'd told me. On a trip back to Bangladesh, his baby son had toppled into a fire, later dying in his arms. “What do you think that does to a man?” his friend Sajid said to me. “Rasul has been through more than most people in a lifetime. See the good he does now in that context.” After his son died, though, Rasul had stopped caring about the game anymore and became a user.

Over the years we had shared an uneasy friendship. During those first weeks and months out of jail, he had told me of his remorse, how he was preparing for the Islamic month of Ramadan and a special 10-day ceremony called i'tikaf [extra prayers, living inside the mosque] to help purge his soul.

We walked towards Bethnal Green. Ahead of us lay a burned out building, testament to Rasul’s fierce power when it came to enforcing his word. A youth had approached us in a side street: the two men swapped an elaborate series of Arabic greetings, before touching the areas above their hearts and ritually embracing. The youth pushed back his baseball cap and made Rasul take his mobile number. “I'm not going to store that,” he'd confided in me, as we moved off. “I just don't want that kind of thing no more.”

When I pressed him, he admitted he had used the other guy – working as a runner for a Yardie gang – to help set up a job, ripping off the Jamaicans (”it was balaclavas and all that, crazy”) and stealing their supply. The youth was kidnapped in response, held until a deal was negotiated between the two groups. The Jamaicans were more concerned with retrieving their two mobile phone numbers, used as their main dealing lines, than anything else: “Worth about 30 grand,” Rasul said, “much more than the drugs.” For years he had lived a life in which retribution seemed to hover around every corner.

A year or so after that I'd seen his hands, the knuckles now terribly misshapen. He'd looked mildly embarrassed. “There's beef innit, round my place,” he spoke, as though it was obvious. Through a flurry of words and sentences, between the dropped letters and sometimes manic flow of words, I made out that dealers – his old workers, the men he now preached against – had been firebombing his place, “testing me”, seeing if he would come out and react (fight them). His fists had reworked their faces. It seemed Rasul’s old life was proving hard to leave behind.

He'd had a difficult childhood, I learned. A father who'd abandoned the family, leaving him as the eldest son to bring up fellow brothers and sisters, his mother angry and confused. He would sigh when talking about it, struggling at times to express himself. From “chillin' and rollin'” as he put it, he then confided how he had once become a gang leader, taking part in what he readily admits was “honky [white] bashing”.

“We were looking for trouble, 'cos they were attacking us. We were so narrow-minded then! One of my friends got sliced in Brick Lane by white fellas. There were a lot of fights back then. We couldn't get along with them and they couldn't get along with us. So we started attackin' pubs, anything, tryin' to scare them off.”

“It went outta control,” he said. “Everyone started fighting, like, with the blacks as well and some of them got too big for the head and doing things. We done planned attacks on the pubs and like, but then everyone just wanted to do their own thing. It becomes like sex.”

He and his friends even fought a cat and mouse game with the ‘Five O’, local cops from Bethnal Green police station, men I got to know in 'ride outs' with their Robbery squad. I would think of this as we strode down Brick Lane from BLYDA (Brick Lane Youth Development Association), the youth project where Rasul had become a mentor and volunteer. Walking with Rasul I could now tell which of the curry house touts were shotting and which not, simply from a glance. He even introduced me to Ruhel, one of his old workers and now a “top shotta” himself: the crew crowded around me in the Sweet and Spicy cafe just at the entrance to the famous road, sizing me up and figuring if I was threat or paying for their time.

Today it couldn't be more different. Rasul is far more calm, more centred. Considering the chaos in his life, the turnaround in his fortunes is remarkable. He runs a youth project, the Rooted Forum, keeping youngsters out of trouble. He is also a drugs counsellor for a local rehab project called Nafas. He has a video production company, has been an NHS smoking counsellor, recently completed an MSc in addiction therapy and celebrated his (Islamic, but not legal) marriage to his second wife.

A “Haji” – one who has been out to visit Mecca, part of the Pillars of Islam – Rasul is also a leading and respectable member of the massive masjid (mosque) in Whitechapel, home to the London Muslim Centre. He even carries out work to prevent the rise of violent extremism. Yet he still has what he calls a "sickness in my heart", the whispering voice of Shaytan, the djinn that most Muslims equate with the Christian notion of the Devil. Constant, five-times-daily Salat (prayer) brings him Tawheed (oneness with God). He rarely misses a chance to be in the womb-like comfort of the building. But his friends seem to be mostly Islamic; mostly non-white.

Others have not fared so well.

Plated for the ghetto

Dog had told me to meet him by the betting shop. It was grey. A carpet of people swept over Whitechapel. They swarmed over its steps, past the Chinese selling their fake DVDs, the Albanian cigarette smugglers, the Cockney stallholders who now swore in Bengali as fluent as their East End patois. Then I saw him. Sauntering, cocky, smiling, his black shades Michael Jackson circa 'Beat It'.

"Yo, s'up bruv?"

"Asalaam Aleikoum, habibi," I replied.

Here he was: Rasul’s former worker Dog, or “MC Dog” as he called himself – proud that he could serve you up whatever you wanted, whenever you wanted it, plated perfectly for the ghetto.

"Why you speakin' Arab for man?" he mocked. "You ain't even Muslim". He sucked through his teeth, disrespectfully.

I told him I enjoyed it. That he could lecture me about halal and haram when he himself had stopped sinning. Like Rasul, Dog reverted (to Islam) inside, sent down on the same charges. Like Rasul he was now out.

“Do you have a problem with that?”

"Nah .. s'just stoopid innit," he said. He looked at me with contempt. Or perhaps eagerness.

"You got it?" 

His voice was demanding. A child-like eagerness flicked behind his thin face and he hunched his shoulders through the windcheater. I nodded. We strode off, taking a winding course through the peoples of Banglatown, as we went to buy him his “wrap”.

I watched as he walked straight into the betting shop near Whitechapel tube station. A couple of minutes later he was out, holding a small package in a tiny piece of plastic, and we were off down a side street.

“Dealers hang out in a betting shop...?” I was incredulous.

“Yeah, perfect innit? It’s like, their office bruv.”

We sat in the back of a car as he unfurled then carefully tapped out the “brown” and prepared the foil. Dog had reverted – but back to drugs, not Islam it seemed. Within moments a flame flared and he was holding the tin foil, then inhaling deeply from the thick, crisp smoke. His eyes fluttered. The finger tips of his small hands danced across his lap, mapping out some unseen land. The acrid scent burned the back of my nose and I felt it too: The Dragon.

Not long after I met Dog, ‘Mo’ crossed my path. A handsome, intense young man, he’d handled the longest sentence of the crew: seven years for his role in supplying heroin and crack on the streets of the Endz. Dog laughed and said Mo had been foolish enough to write all his deals down, ensuring his downfall. He always seemed angry whenever we met.

"I bunked off school, then I started smokin’ drugs, sellin’ drugs, then I went to prison and I came out about a year ago... that's my story,” he growled, when I first asked about his life. Like his friend and former rival, Rasul, with whom he’d once fought a crazy war, Islam had entered his life in jail.

Yet he seemed most animated whenever we discussed the past: the fast life of cash and women that came with the easy money that drugs could supply to these Bengali soldiers.

"I used to hang ‘aat [out] with prostitutes, they were my bitches, we used to smoke drugs together. I can’t stand ‘em now.” He told me how he and his friends would wait "for like some victim to come, a punter, then we'd all rush 'im and get 'is money. That's when Vallance Road was hot: ‘hos [whores], gangs, drugs."

Again, I would meet Mo – who renamed himself to the more Islamic-sounding Abdul Rahman – during my trips to meet the old gang members. We broke fast together during Ramadan, eating the succulent dates and pieces of sweetcorn, washed down with water, that reminded the faithful of how their Prophet had done so 1400 years before. I was surprised when he told me that he too had joined BLYDA; he was a mentor to gang members but was finding life difficult.

We walked out into the playground surrounding the centre. Fat drops of rain begin to fall. Mo’s shoulders sank. “Going straight is hard. ... It’s the money man. Don’t get me wrong: being a mentor has given me new direction. But it’s so annoying, so frustrating,” he lamented. “The kids just won’t listen. ‘Naw man, for real! They don’t.”

Rasul had told me that they both worked hard to steer the youngsters in their area away from drugs and crime. “I listen to them,” he said, with an edge of importance. “They’ve got no-one they can listen to. I use the experience I’ve gained growing up. Just to let them know they don’t have to go down the wrong track. I had to learn the hard way. There was no-one like this around.”

It was only much later I had learned they had fought a war together. These brothers of the Umma had once been pimps. “Yeah, y’know Mo, he did a ‘hit’ on my house,” admitted Rasul when I asked about it.

They had kidnapped each others’ workers. Mo had tortured one of Rasul’s people for several days. The guy jumped out of a second floor window to escape. “He hobbled home,” laughed Mo when telling me about it. “The flat was covered in blood.” He spoke in the same casual manner about violence I had come to associate with the neo-Nazi gangs and football hooligans I had once investigated for my book, Homeland.

The last time I saw him he was smoking a shisha pipe in one of the halal Islamic cafés that have sprung up in the Endz. He was with another young man out on probation. Together they ripped into the politicians now making the East End their battleground. They seemed to hate George Galloway, who had made Muslims his friend, more than most: "He's like you, man,” sneered Mo. “He's one of you, a replica of one of you! An old version with a cigar, yeah?"

The police remained the enemy. And he wanted, he said, to wipe out everyone that “came in the way” of Muslims.

“That's what I want to do bruv! These people need to be taught a lesson!"

Tight, confused

“These kids, they're out of touch with our culture: the elders have lived one part of their life abroad and don't understand the younger Bengalis around them,” says another Bengali friend of mine, who for years has worked with young men into gangs and drugs. “Many parents still want to arrange marriages for their children or try to send them back to Bangladesh if they misbehave. But it doesn’t always work.”

“We are tight, close. But we are also confused.” He tilts his head and sighs. “I have my father and mother's culture to uphold, and Western culture too. I turn on the TV and I hear about Islamophobia. How do you balance all of these factors?”

Today Dog sits in jail. Mo too. Rasul doesn’t want me contacting them. He has moved on: “the brothers” have not. Meanwhile, when we last met, he was full of excitement. He'd just been on a demo at the Israeli embassy in London, taking a couple of friends with him who were "up for it" – until they saw the security guards from the (Jewish-run) Community Security Trust. "We need something like that here, man. Something for our own community."

He was still incensed over the wars in Palestine, Iraq and Afghanistan. It was time for "Muslims to take back Al-Aqsa [mosque, in east Jerusalem]," he said. The next I knew he was in Gaza, with George Galloway, taking a humanitarian convoy overland from Egypt to the Palestinians.

Another friend of mine, an ex-extremist himself, says that there is an increasing intolerance of “other forms of Islam” at the East London Mosque where Rasul and his cohorts have worshipped; “one can never be critical of Hamas there,” my friend said. When he looks around him, he sees former friends now moving into these circles, political Islam, and says: "Before, they were rebels without a cause... now they’re rebels with one."

Meanwhile the hoardings have gone up, the old buildings come down: the foundations are being laid for the greatest sporting spectacle the world has ever seen. In just three year’s time the East End will be changed, perhaps forever. Who can say what this will bring for the children of the Abyss – or whether those, such as the men grasping the Qu’ran for salvation, will be around to see it?

This story was commissioned for Esquire ©2009.

Photo ©Simon Wheatley