Many hope to leave the hardship of London's streets behind them
A blue Mercedes minibus in London is packed full of Polish workers poised for a journey across Europe to a new life in a distant land.
But these are not economic migrants - not now anyway.
These passengers are the casualties of mass migration, and they are going home.
More than 800,000 central and eastern Europeans have registered to work in Britain in recent years, and the unofficial figure is probably much higher.
But when temporary work dried-up, many ended up homeless and on the streets - many by now with drug or alcohol problems.
A recent survey found 18% of London's rough sleepers are now eastern and central Europeans.
Twice a month a Polish Charity, the Barka Foundation, carries some of the most vulnerable cases from London back to Poland for detoxification, voluntary resettlement and retraining.
The charity's co-founder, Barbara Sadowska, said she was shocked that such a "massive number" of Polish people were in such a "tragic situation in London".
In Poland the Barka charity runs a series of organic farms, it has connections with a sawmill, and is setting up a pasta factory in the bleak countryside outside Poznan where the London returnees can work and rebuild their lives.
Adam slept rough in London, and spent time in mental institutions
I took the journey home with them, and after picking up temporary papers for those with no documents at the Polish Consulate, we headed out of London guided by a Polish "sat nav" system, destination Poznan.
On board were two street drinkers, both recovering from building-site injuries, a homeless heroin-user taking methadone to sustain him on the trip, a former mental patient who has been sleeping rough and a woman too traumatised to tell her story.
Swavek had earned good money as an electrician until his fingers were almost severed by plate glass on a building site.
He has praise for Britain's National Health Service, but that is about all.
Fighting for compensation
He was unable to work for eight months and his family in Poland sent him money to survive after his injury.
He ended up first squatting, and then on the streets, where he turned to alcohol.
In his time, he says, he opened 98 squats in London.
He is still fighting for compensation for his injury.
Piotr was injured when scaffolding collapsed on a building site.
And when casual work dried up, he ended up sleeping rough, knocked out by cheap cider.
At just 35 he would pass for 50, his hands and face are badly scarred, and he has a ruddy, drink-soaked complexion.
Daniel is tall and deceptively jovial, though a little "spacey".
He ended up on heroin and crack cocaine - a habit he says he funded by shoplifting and street theft.
He says he was caught 14 times and imprisoned twice, and now says he wants to go home to his family.
Then comes Adam who did not want to give his real name. He is talkative and persistent.
The landscape outside Poznan is decaying and bleak
He wears a Paddington Bear hat and thick sunglasses in winter.
There is talk of noble connections, and he carries a silver ring in the shape of a rose for the woman he calls his "princess".
He spent time in mental institutions after an altercation in McDonald's.
He too was sleeping rough but his words do not quite match his experience.
"I have had a great time in England," he says. "I'm still alive so I feel marvellous.
"People in mental health institutions are just more fragile," he adds.
On the cross channel ferry our two drinkers, denied alcohol on the journey, are noticeably suffering.
Both are sweating and in Piotr's case shaking too.
He spends much of the motorway journey across Europe slumped, glass-eyed, in the corner, barely able to speak.
Polish sausage is passed round as the French motorway stretches into the night and the minibus devours the kilometres.
I am accused of hogging the heater, but my shoes have melted and I am happy to swap places.
We arrive late next morning at a former state-owned farm.
The landscape is decaying and bleak but there is a warm welcome.
Food in lavish quantities is on offer; the greeting breakfast is a key part of the Barka resettlement strategy.
Over the next few days, I meet numerous ex-London Poles - all had returned with heavy drink problems, and all say they have kicked the booze and started again.
If you take Alcoholics Anonymous, add a twist of Christian charity, set it all in a 1970s workers co-operative on an organic farm, then you have the Barka foundation recipe.
It is personal and engaging, but I cannot help wondering if it is not the flat, monotonous landscape and decaying villages that led many to flee in the first place.
The Barka foundation is driven and idealistic but it cannot compel people to stay.
Within an hour of arrival, Daniel, who is still on methadone, heads off to the nearest city, saying the small village is too "quiet".
He prefers to detox with his family, he says in broken English.
"He should deal with his drug problem," says the Barka Foundation's Marysia Starzewska. "But we can't force people," she observes.
Adam goes too.
Ready to try again
At a sawmill I meet a hard-working, lively looking woman, who returned swollen-faced from London several months ago.
Ylana drank so heavily that when she first detoxed, she did not recognise anyone she had spent the previous months with.
The greeting breakfast is a key part of the resettlement strategy
Her life is stable now that she has stopped drinking, but I gasp when she tells me she is ready to go back to London to try again.
"I feel I am young and I can still do a lot of things," she says. "I want to go out into the world and do things, and I believe I can do it in London."
"We are saving their lives," says Marysia Starzewska, "because many people have died on the streets." But she adds: "It is shocking that they still want to go to London. I think some of them are really desperate."
As the new arrivals tour the Barka facilities, people listen opened-mouthed and in shock as their hellish tales of life in London unfold.
They tell of fake job agencies, industrial injuries, shoddy building techniques, soup kitchens, low pay, no pay, exploitation and relentless street drinking.
Britain emerges as a dangerous and hostile place, for these are the victims of a "cash-in-hand" economy.
But with pay rates much higher in Britain, the lure is still strong.
Barka's co-founder, Barbara Sadowska, describes the EU expansion which allowed her fellow countrymen to work in Britain as a new Marshall Plan, and a "great success for Poland", allowing Poles to accumulate some capital.
But she concedes the mass migration that followed has been a "big social experiment with big social costs".
And she is critical that homeless charities in London feed and clothe people without doing enough to tackle their alcohol problems.
The Barka bus offers a lifeline, and she maintains that no-one has returned to Britain after recovering.
That is hard to verify and anecdotally it is disputed.
Within hours Piotr has warmed to the welcome, and committed himself to stopping drinking.
Swavek, who said he was drinking heavily in London, thinks he can handle it alone.
Maybe he can, at least now that the hardship of London's streets are just a distant memory.