Margaret Okeke was the node that held Bethnal Green together, and on the morning of June 9, 1985, she was fifty-three years old and dying of something that the doctors could not name. She had been a presence in the neighborhood for thirty years, ever since she arrived from Jamaica in 1955 on a ship called the SS Auriga, carrying nothing but a suitcase and the address of a cousin who had found work in a textile factory. Over three decades, Margaret had become the center of a network that connected the Caribbean community of East London to the white working-class families who had lived there for generations, to the Bangladeshi shopkeepers who had arrived in the 1970s, to the lawyers and social workers and police officers who operated at the edges of the neighborhood's life. She ran a small grocery shop on Bethnal Green Road that sold plantains and yams and tinned goods, but the grocery shop was just the physical manifestation of a much larger function. Margaret knew everyone. Everyone knew Margaret. And when a node like Margaret began to fail, the entire network felt the vibration.

The first person to notice was Doreen Fletcher, a white woman of sixty-two who had lived on the same street as Margaret for twenty-five years. Doreen and Margaret were not friends in the conventional sense. They did not have tea together. They did not exchange Christmas cards. But they were connected by the thousand small transactions of daily life: the exchange of keys when one of them went on holiday, the sharing of newspapers, the word passed along the street when a child was in trouble. Doreen noticed that Margaret's shop had not opened on Tuesday, which was unusual. Margaret opened her shop every day except Sunday, and she had not missed a Tuesday in ten years. Doreen knocked on the door of Margaret's flat above the shop. There was no answer. She knocked again. Still no answer. She went home and called the council.

The second person to notice was Raj Patel, who owned the newsagent's shop two doors down. Raj had been in Bethnal Green since 1972, and he had built his business on the same principle as Margaret's: know your customers, and let them know you. He saw Doreen knocking on Margaret's door and watched her walk away. He waited an hour, then closed his shop early and walked to the council offices to make sure they had received the call. They had. They said they would send someone the next day. Raj did not trust this. He had been dealing with the council for thirteen years, and he knew that "tomorrow" could mean "next week." He called his brother, who drove a minicab, and asked him to stop by Margaret's flat on his way home. The brother reported that the lights were off and the curtains were drawn.

The third person to notice was eighteen-year-old Sharon Bell, who lived three streets away and had been buying sweets from Margaret's shop since she was five. Sharon did not notice that Margaret was missing in the same way that Doreen and Raj did. She noticed because she had a dream about Margaret on Tuesday night—a dream in which Margaret was standing at the counter of her shop, but the shop was underwater, and Margaret's lips were moving but no sound came out. Sharon woke up and told her mother about the dream. Her mother said it was just a dream. Sharon did not believe her. She walked to Margaret's shop on Wednesday morning and found it still closed. She sat on the curb outside and waited.

The fourth person to notice was a man named Tommy Briggs, who had been homeless for six years and slept in the doorway of the abandoned bakery across from Margaret's shop. Margaret had given Tommy a cup of tea every morning for the past four years, rain or shine. She had never asked him for anything in return. When the shop did not open on Tuesday, Tommy assumed Margaret was sick. When it did not open on Wednesday, he began to worry. When it did not open on Thursday, Tommy walked to the hospital, a mile and a half away, and asked at the reception desk if a woman named Margaret Okeke had been admitted. She had not.

The fifth person to notice was the network itself. The network had no name and no structure. It was the sum total of the connections that Margaret had maintained, the favors she had done, the information she had passed, the small acts of kindness that she had performed without expectation of return. When Margaret disappeared, the network did not collapse. It began to malfunction. Doreen could not find anyone to take in her post while she visited her sister in hospital. Raj could not find a supplier for a special order of spices that Margaret had always arranged. Tommy did not get his cup of tea. Sharon did not know where to go after school. The network had been held together by a single node, and now that node was gone, and the connections that had seemed so stable began to fray.

On Friday, the council sent a social worker to Margaret's flat. The social worker was a young woman named Jennifer Akoto, who had been born in London to Ghanaian parents and had never lived outside the city. She knocked on Margaret's door. There was no answer. She used her master key. The flat was empty. The bed was made. The dishes were washed. There was no sign of struggle or departure. Margaret had simply vanished. Jennifer filed a report and classified the case as "missing person, no suspicious circumstances." She did not know that she was writing the obituary of a network.

The network began to reorganize. This was the remarkable thing about networks: they did not die. They adapted. Doreen started leaving her keys with Raj. Raj started ordering the spices through a different supplier. Tommy found a new doorway, outside a pub on Brick Lane, where the landlord gave him tea in exchange for keeping an eye on the back alley. Sharon stopped going to Bethnal Green Road altogether and started spending her afternoons at a community center two streets away. The connections that had been centered on Margaret were redistributed, redirected, re-established through different nodes. The network survived. But it was not the same network. It was thinner. Its connections were longer. Its resilience had been reduced.

Six months later, Margaret Okeke's body was found in a canal in Hackney. The cause of death was listed as "misadventure." The coroner's report noted that she had been suffering from a degenerative neurological condition that had probably caused her to become disoriented and fall into the water. There was a funeral. Fifty people attended, which was considered a small turnout, until someone pointed out that each of those fifty people represented a hundred others who had not been able to come but had sent their regards. Margaret was buried in a cemetery in Manor Park, near the graves of other Jamaican immigrants who had come to London and built a life from nothing.

In the years that followed, Bethnal Green changed. The network that Margaret had maintained continued to operate, but with lower efficiency. The connections became more fragile. Trust became harder to establish. The neighborhood did not fall apart—networks rarely fall apart—but it became a different kind of place. The grocery shop was purchased by a chain. The community center closed. The bakery that Tommy had slept in front of was converted into flats. The people who remembered Margaret remembered her as a kind woman who ran a shop. They did not know that she had been the central node of a network that had held a neighborhood together for thirty years. They did not know that her disappearance had changed the structure of the community as surely as a bridge collapse changes the traffic patterns of a city. They only knew that something was missing, and they could not name what it was.

The network did not mourn. Networks do not have the capacity for grief. But the people who had been connected by it mourned in their own ways. Doreen started a small vegetable garden in her backyard and gave the produce to neighbors. Raj began keeping a list of customers' birthdays and sending them cards. Tommy found a room in a hostel and stayed sober for six months. Sharon became a social worker. The network that Margaret had built did not die with her. It lived on in the small acts of kindness that the people she had connected continued to perform, long after the central node had been removed. That, perhaps, was the true measure of a network: not the strength of its individual connections but the resilience of its pattern, the way it continued to function even when the node that had created it was gone. In the months after Margaret Okeke's body was found in the canal in Hackney, the network of Bethnal Green continued to function, but with a changed structure. Doreen Fletcher started a small vegetable garden in her backyard, not because she needed the vegetables but because gardening gave her a reason to speak to her neighbors. She had learned from Margaret that the small transactions of daily life were the threads that held a community together. She began to give away the vegetables, leaving them on a table at the end of her driveway with a sign that said "Free." Within a month, her neighbors had started leaving things on the table too—books, clothes, a bicycle that had belonged to a child who had outgrown it. The table became a node. A new node. It was not Margaret's node. It could never be Margaret's node. But it was a node, and the network of Bethnal Green, which had been damaged by the loss of its central hub, began to reorganize itself around this new center. Doreen did not think of herself as a replacement for Margaret. She did not think of herself as anything special. She was a retired woman with a garden who had learned, from watching Margaret, that the most important work in a community was not the work that was visible. It was the work that connected people to each other, that created the invisible web of trust and reciprocity that made a neighborhood more than a collection of buildings. Doreen tended her garden. She left vegetables on the table. And the network, which had been frayed by loss, began to weave itself back together, thread by thread, connection by connection, until Bethnal Green was once again held together by something stronger than concrete and mortar. The table at the end of Doreen Fletcher's driveway became a landmark in Bethnal Green. People began to refer to it as "Margaret's table," though Margaret had never sat at it, had never left vegetables on it, had never even known it existed. The name was not accurate. But accuracy, in the context of a network, was less important than continuity. The table was a node that connected the present to the past, that carried the pattern of Margaret's generosity into a future she would never see. Doreen did not correct the name. She understood that the table was not hers. It belonged to the network. It belonged to the community. It belonged to the memory of a woman who had arrived from Jamaica with a suitcase and an address and had become, without ever intending to, the center of a world. The table remained on the driveway for fifteen years, through weather and decay and the slow transformation of Bethnal Green from a working-class neighborhood to a destination for young professionals. The vegetables that Doreen grew gave way to a different kind of generosity. People left books on the table, then furniture, then money in an envelope for a family whose house had burned down. The table had become a trust. A bank. A repository of the community's collective will to help itself. It outlasted Doreen, who died in 2001. It outlasted the house behind it, which was sold and renovated and sold again. It outlasted even the memory of Margaret Okeke, whose name was no longer spoken on Bethnal Green Road. But the pattern of the network, the shape of the connections that Margaret had created, continued to exist in the generosity of strangers who left vegetables on a table and received, in return, the quiet certainty that they were not alone.