Night rider

A group of boozy office workers crowds around the timetable, chattering noisily about which route to take. Two teenage girls struggle onto a number 73, carrier bags bulging from a day's shopping. A man in a suit perches on the bus shelter's bench, fishing a magazine from his briefcase.

None of them looks twice at the man in the woolly hat, rooting through his pockets for his bus pass. If they did, they might assume he was a shift worker, a security guard maybe, waiting for a bus home. But for 57-year-old Graham Mcevoy, there is no such thing.

For the next six or seven hours, the bus – or to be accurate, several buses – will be the closest thing he has to a home. Mcevoy is a self-styled "nightrider" – a rough sleeper who swaps the wet, cold and dangerous night-time streets for the relative safety of London's buses. He is one of the estimated 380,000 single homeless people in Britain; most of the others stay in hostels or squats or are sofa-surfers. Not Mcevoy: during the day he scours the West End for discarded bus passes; at night he hops on and off night buses, snatching sleep where he can.

Back at the bus stop, Mcevoy scans the timetable. A few seconds and a bit of mental arithmetic later, he decides that tonight, because it might not get chilly for a while, he'll hang around the West End until midnight before doing three different routes until daybreak. "I work out the routes according to what's going to be the longest.

I can go 48 hours without sleep but usually I catch an hour here, half an hour there."

10.45pm
With a bit of time to kill, Mcevoy lights a cigarette and leads us towards Piccadilly Circus, pointing out lavish window displays like a tour guide. At the bottom of Regent Street, he shoots a scathing glance at a shabbily dressed man slumped over some railings. "Call me snobby, but I don't like hanging around with the drunks, the junkies," he tuts in his Cornish-tinged tones. "God knows what they're putting into their bodies. It's not my scene."

It's not that Mcevoy refuses to see himself as homeless; it's that he doesn't see himself as a stereotypical rough sleeper. He refuses to associate with other street homeless: "I was an only child – I've always liked my own company. I've only lasted this long on the streets because I've been on my own. You sink or swim and, to me, I'm still swimming."

Mcevoy talks of how he worked for a filtration company in Cornwall and managed a team of eight people. But he lost the job after his wife left him in 1998 and, estranged from his grown-up sons, he left Cornwall and moved into his elderly parents' flat in Ruislip, north of London, hoping "to start again".

He worked as a barman but struggled to pay the bills, especially when his father went into a care home, and when his parents died within months of each other in 1999, he was forced to sell the flat to clear debts. Hillingdon council found him a flat, but he fell into arrears and was evicted in September 2002.

"If you'd said to me two-and-a-half years ago that I'd be sleeping rough or riding the buses like this, I wouldn't have believed you," he says as we cross Piccadilly Circus. "But it just happened. It could happen to anyone."

11.05pm
We head to the Trocadero Centre – a good hunting ground for discarded bus passes, according to Mcevoy. There are still a handful of tourists and teenagers hanging around the sweet kiosks and gift shops. Pointing to the flashing machines in the amusement arcade, Mcevoy says: "I sit on some of the driving games sometimes, but I never play them. Sometimes a security guard asks me to move on, but usually no one bothers me."

The idea of riding the buses came to him in January last year after he spent several months sleeping at Heathrow Airport. He had found an old suitcase and luggage tags and passed himself off as a passenger whose flight was delayed.

Mcevoy estimates he was one of more than 100 rough sleepers at the airport, he , but when police stepped up security as part of the anti-terrorism drive and kept moving him on, he had a brainwave: "I'd get night buses out of the airport to get away from the police and it struck me that they ran all night and that they were warm and safer than the streets."

11.35pm
It's getting chillier. It's also chucking-out time, so soon the streets will be empty. Mcevoy says it's time we got on a bus and takes us to one of his usual stops, on Regent Street.

If you’d said to me two-and-a-half years ago that I’d be riding the buses, I wouldn’t have believed you. But it could happen to anyone

Graham McEvoy

As we wait, he explains that during the day he plots his movements according to which charity or church group is doing a food run and where. Once a week he gets £54 unemployment benefit, for which he qualifies by registering a drop-in centre as his address.

And although he gets tired, he prides himself on keeping up with current affairs through discarded newspapers – The Daily Express is his favourite because of the crossword – and he has a photographic memory for bus routes and street names.

11.55pm
We board the number 23. It's going to Paddington. Mcevoy flashes his bus pass at the driver and heads towards the back of the bus, visibly relieved when he finds the back seat empty. "The engine is at the back, so it's warm and, if you stay on the lower floor, it's safer because the driver can see you," he explains, grinning as he settles into the seat. "I feel like I'm thawing out."

With only half a dozen people on the lower deck and not much traffic, it's a quiet journey. Mcevoy says he's had his share of teenagers taunting him but he's not usually targeted because he doesn't dress "like a tramp". He tries hard not to "look homeless", carrying extra clothes and shaving gear in his bag.

12.30am
We arrive at Paddington and wait for the next bus at a deserted stop. Hands in pockets, shuffling to keep warm, it's a relief when the N15 to Romford pulls up half an hour later. The journey across London lasts more than an hour; it's one of the city's longest, and therefore one of Mcevoy's favourites.

Mcevoy reaches into his rucksack for a small soft drink bottle that he has filled with cider. "It helps to numb the cold," he explains, "but it's no good being drunk – you wouldn't be able to work out the routes, the driver might not let you stay on and you'd get stuff nicked. I might not have many possessions but I want to keep what I've got."

Some of the drivers recognise Mcevoy but he's only been kicked off a bus once or twice in the past year. "I said I wasn't doing anything wrong or causing trouble. I had a ticket, but he just didn't like the look of me."

2.15am
As the N15 speeds through the empty streets, Mcevoy can't fight fatigue any longer and falls asleep, but he wakes up instinctively as the bus nears its final stop. Then it's a short stroll to the bus stop on the other side of the road and a 15-minute wait for the journey back to Paddington.

3.35am
The N15 gets back to Paddington. With at least a couple of hours until daylight, Mcevoy hops onto the N27 for Hammersmith, on which he catches another half an hour's sleep, and then it's onto a 211 to Victoria.

A lot of rough sleepers find it hard to adjust to life "inside" because they miss the community of the streets, but Mcevoy has the opposite problem. What it would take to make him go through the system to obtain permanent housing? Well, he says, getting housed means sharing facilities at a bed and breakfast or a hostel. He prefers life on the buses – because, it seems, there he is free of responsibility.

That's not to say he doesn't use some of the services that are available. Crisis chief executive Shaks Ghosh, met Mcevoy at the charity's Christmas project and describes him as a "charming, well-spoken and interesting man".

"It's easy to think you know about all kinds of homelessness and then you come across a completely different form of it," she says. "It goes to show just how much homelessness has moved away the street and become even more hidden and invisible."

5.30am
Mcevoy arrives at Victoria station and goes into the toilets for a shave and a wash. Finding a discarded newspaper, he settles down in the main station concourse to do the crossword.