It's raining slightly, drizzly and generally grey and Oxford Street is milling with an early lunch crowd. English college students and office workers weave in and out of shoppers, dodging umbrellas and puddles on the pavement. People are huddled under the bus shelter. All sheltered seats are taken and people stand close to the knees of the seated people. Their proximity is mirrored by the mass of people circulating around them.

A No.73 arrives. People clamour off the middle door and in the front door. It is a closed bus. When Routemasters are not available a double crew take out a newer bus. I can see the male driver but a female conductor blocks his access to passengers. She is about 45 years old, has long grey hair in a ponytail and is wearing the Arriva uniform of blue loose trousers, white shirt with a yellow safety vest. She wears fingerless leather gloves and has a ticket machine slung around her neck. Most people before me already have travel passes, as do I. She nods and clicks a button on the machine as I pass. I walk up the stairs with three others ahead of me and move to the back of the bus.

I notice everyone sits as far as possible from others already seated. And where there is space people who know each other sit separately as well. There are 13 people up the top. With eight double seats on the right and ten on the left plus a bench back seat that joins both rows. Everyone is looking out the windows – either just with their head turned or in some cases their entire bodies are twisted.

Two young men, about mid twenties, are seated on separate seats across from me at the back. They are both are turned to the window. Dressed in casual jeans and t-shirts, they both have small day packs on the empty seat next to them. One is wearing a tan baseball hat turned towards the back and the other has almost yellow dyed hair.

I can see little of their faces. They are talking very loudly in an Asian language, laughing, overlapping each other, arguing. At first I think they are both on mobiles, speaking into hands-free ear pieces as their voices are raised and they both stare out the window. Yet they are speaking to each other without any face to face contact. They physically appear strangers on a bus except for the sounds of their voices.

A boy about 17 or 18 is sitting in front of one of the talking men. He is the only passenger sitting alone who sits on the aisle side of the seat. Everyone else has taken the window side of the seat. He has a closely shaved head and is wearing a Nike waterproof jacket, pinstripe trousers and I glimpse shiny black shoes that seem to be part of a work uniform. He turns around every time the conversation by the two men behind reaches a peak or they laugh. His body language indicates annoyance as he turns several times. His irritated body twist is not enough to confront them but enough to indicate he is aware of their noise. Because the two men are staring out the window, neither notice his movements.

Three men walk up the stairs and sit in the middle left seats. Two sit together and their friend sits behind close to the window. They are all dressed in long sleeve shirts; two are purple, one is white. They talk together, faces occasionally facing but most often all are staring out the left windows. Their collective voices are barely audible over the engine sounds and the two men talking at the back of the bus near me. When the bus turns past Marble Arch, they all stand and take seats on the right hand side of the bus in order to look at the park.

The two talking men near me grab their bags and talking all the way to the stairs at the front, get off the bus at Marble Arch. Not once do they turn to face each other as they walk along the aisle and down the stairs. Their bodies disappear before their voices do.

It seems quiet in the bus even though the engine is very loud. The talking men's voices had dominated even the grinding gear change and brake sounds of the bus.

As the bus travels down Park Lane, the boy stands up and drags a large rectangular suitcase out from seat next to him. It was the reason he was sitting on the aisle edge of the seat. It looked very awkward and heavy as he struggled with it. He tried at first to walk with it in front and then behind and then ambitiously tried to put it onto one shoulder. It hit the ceiling of the bus. In the end he half pushed, half carried it to the stairs and left the bus.