On a drizzly afternoon in February, Philip Kelly made the short drive from his home near the centre of Derby to a street in Normanton, one of the poorer areas of the city. He stopped at one of the terraced houses owned by G4S, which has a government contract to provide housing to asylum seekers in the region. The upstairs flat was occupied by Said Ghullam Norzai, an asylum seeker from Afghanistan, and his 11-year-old son, Wali Khan.

Kelly knocked on the door, but there was no answer. Said and his son had vanished. Almost two years after smuggling themselves into the UK in the back of a lorry from Calais – and just seven weeks before an asylum appeal hearing that might have allowed him to stay and work legally in the UK, Said had smuggled himself and his son back out of Britain.

Said had arrived in the UK in May 2016, after a long, terrible journey from Kunduz province in Afghanistan. It took him almost a year, during which he was separated from his wife and their other children. More than a million people arrived in Europe by sea in 2015, of whom 50% were estimated to be Syrians and 20% Afghans.

A farmer and a family man, Said struggled with his new life in Derby. Here he was in an industrial city thousands of miles from home, confronting a world of bureaucracy in which his life was defined by Home Office letters, solicitors’ meetings, healthcare forms and strict school pick-up times. “I’m a simple man. I’m not educated,” he would often say, with a shrug.

Kelly first met Said and his son in the summer of 2016, when he knocked on their door to deliver a welcome box containing clothing, toiletries and toys – part of his work as a volunteer “befriender” for a charity called Upbeat Communities. Since that first meeting, Kelly, a middle-aged engineer, had been their primary support in Derby.

Said came to rely heavily on Kelly, who took him to doctors’ appointments and meetings with a solicitor to discuss his asylum claim. When Said, who is illiterate in English and his native Pashto, received post, Kelly would take Said into town to visit Aslam, an Afghan-British shop-owner, who would translate it.

It was thanks to Kelly that Wali Khan was enrolled in the local primary school. Said received a list of schools when he arrived in Derby, but did not understand the enrolment process. When Kelly visited one day and found the boy at home with his father, he scrambled, calling round local schools until he found one that had a free place.

Kelly was calling in on Said that day in February to check he had received an NHS form that would allow him to get new glasses, and to find out why he had missed a meeting with social services the previous week. As he turned to leave after getting no answer at the door, he saw a police car pulling up. “I thought, oh I’d better stay and see what this is about. I wonder if Wali Khan is in trouble or something,” Kelly recalled. The police told him that Wali Khan hadn’t been at school, and that they had a suspicion that he was not living at the property. They wanted to break the door down.

Kelly convinced the police to call G4S instead, and an employee came with keys to the house. Inside, they discovered that Said’s bed, the washing machine and a wardrobe – all of which were owned by G4S – were missing. There was a receipt for a transaction in which someone had converted 1,000 euros into pounds.

The scene was mystifying, but one thing was clear: Said and Wali Khan had gone.

Dates are not Said’s strong suit. He has only a rough idea of his and his children’s ages, but he believes he set off from Afghanistan in September 2015. He left home with his wife and their seven children – then aged somewhere between one and 15.

According to the account he later gave to the Home Office, Said fled his home in the Chardara district of Kunduz province because he was being harassed by the Taliban, whose power was growing in the area. They had been coming to his village in the middle of the night and shooting at people. One night they visited Said’s home. They threatened him, smashing up his property and demanding that he spy on government forces for them. “My children were frightened and said, take us away from here,” he said during his asylum interview. “Our province has no security. There is no peace. My home was destroyed. Everything is destroyed.”

As for so many who have made that perilous voyage to Europe, Said’s journey was unthinkably difficult. He and his family were among a group of about 100 people who had paid smugglers to take them across the mountainous border between Iran and Turkey when unseen attackers began firing on them. As the shooting started, Said was holding Wali Khan’s hand, and they ran and hid together. But when they emerged, there was no sign of the rest of the family. The smugglers said they had gone on ahead, and they needed to keep moving.

Said and Wali Khan made it to Turkey, where Said thought he would be reunited with the rest of his family, but again he could not find them. He has had no word of his wife and six other children since.

Not long afterward, Said and Wali Khan crossed the Mediterranean in an inflatable boat. (In October 2015, around the time of their journey, 221,000 people made that same perilous sea voyage, more than in any other month that year.) Eventually, after walking across Europe, through countries whose names Said does not remember, and then spending six months in the migrant camp at Calais, he and Wali Khan stowed away in the back of a lorry and arrived in the UK in May 2016.

When I first visited Said in Derby in February last year, to make a film about him and his son for a Guardian project called the new arrivals, he had not seen his family for more than a year. “When my son comes home at night, he asks me: ‘Where is my mum, my brother and sisters?’ If I had known I was going to lose them, I would never have left,” he said.

Said had been convinced that once he reached the UK, his problems would be over. Britain would give him papers, and help him find his family. He thought the battle had been to get here. He did not realise what kind of battle would be involved in trying to stay.

The process of becoming a refugee in the UK goes like this: after someone arrives in the UK (or someone already in the UK learns it would be dangerous for them to return home), they present themselves to the authorities and ask for asylum. At this point, they are classed as an “asylum seeker”: they are not officially a refugee until their asylum claim is successful. To obtain refugee status, you must lay out your claim in two separate interviews with the Home Office. Said had the first of these – a “screening interview” – on 27 May 2016, the day he arrived in the country.

Said unwittingly created problems for himself from the outset. At the screening interview – a brief session designed to collect biographical data and the basic outline of someone’s claim for asylum – Wali Khan told the Home Office he was nine years old. Since he and Said did not know their birthdays, they were assigned a birthdate of 1 January – like all asylum seekers who do not know their date of birth. (The producer and interpreter I worked with on this project, Shoaib Sharifi, who is British-Afghan, estimates that 80% of Afghans in the UK, including himself, have that same birthday.)

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This invented birthday meant Wali Khan was officially nine-and-a-half when he arrived. Liz Clegg, a former firefighter who spent two years living in Calais and got to know Wali Khan and his father there, is convinced he was only seven or eight at the oldest when he arrived in the UK. This confusion would have led to Wali Khan being put in the wrong year at school – and moreover, Clegg said, such an apparently cavalier attitude to dates and years is likely to have been regarded by the Home Office as deliberate falsehood.

Said and Wali Khan were sent to live in a hostel in Birmingham, and then eventually to the flat in Derby. Asylum seekers who have no means of supporting themselves – roughly half of them – are provided with accommodation and a weekly allowance (at that time, £36.95 per person; it was increased by 80p to £37.75 in February this year) while they wait to hear about their asylum claim. During this time they are not allowed to work.

The next step in the asylum process is the “substantive interview”, which is conducted by a Home Office caseworker. This is an asylum seeker’s main chance to lay out the reasons they should be granted asylum. Said’s substantive interview took place in Birmingham on 10 November 2016, four and a half months after he arrived in the country. It took four hours. And it was a disaster.

It is hard to overstate the importance of the substantive interview. Because most asylum seekers are not able to bring documentary evidence proving the danger in their homeland, their claim is often decided based on how believable their story is. Miranda Butler, a barrister who specialises in immigration law, described the Home Office interview as a “totemic piece of evidence … If you’re given one chance to tell your story, you’ve got to give your claim in a watertight fashion. It’s very difficult to change your account afterwards – and if you do, people will assume you’re lying.”

Just 32% of initial asylum claims decided in the UK in 2017 resulted in someone being granted refugee status or another type of protection visa. Of all the initial refusals that went to appeal, 35% were overturned by a judge. In cases involving people from Afghanistan, it was 52%.

Though asylum seekers are entitled to a legal aid solicitor to help them with their case, Said went to his Home Office interview without ever having seen one. When I asked him why, he said he didn’t know. Kelly’s guess is that when Said was given a list of solicitors, while he was in the hostel in Birmingham, he assumed that one of them would represent him; much as he assumed that being given a list of primary schools that Wali Khan could be enrolled in meant that Wali Khan was enrolled.

Kelly travelled with Said to his interview that day, and remembers that when Said came out of the interview room holding the transcript, he was upbeat. “He was really chipper, he was saying that now he’d get his family over, and the rest of it,” Kelly recalled. “I read the transcript on the train going back with him, and I thought: ‘Oh my God. It’s terrible’.”

Facebook Twitter Pinterest Philip Kelly, who acted as a volunteer helper for Said and Wali Khan. Photograph: Christopher Thomond/The Guardian

Said’s interview transcript shows that he was asked about the threats made to him by the Taliban – which might have helped him qualify for protection under the 1951 refugee convention – in an almost perfunctory way, though the Home Office interviewer repeatedly tried to get more information from him. Instead, Said dwelt on a feud he had with another individual in Kunduz. His responses were confused and hard to follow. Crucially, he did not fully explain discrepancies between his replies to that day’s questions and what he had said in his screening interview five months earlier.

I have seen Home Office refusal letters in which the caseworker has noted very small inconsistencies between screening and substantive interviews, and taken them as evidence that the person “lacks credibility”. One such letter dismissed a man’s claim that he had been attacked because in his screening interview he said he was shot in the leg, and in the substantive interview he said he had been shot in the foot. “As an educated person it is not unreasonable to expect that you would know the difference between your leg and your foot,” the caseworker wrote – this despite the facts that English was not the asylum seeker’s first language, and his interview was conducted without an interpreter. In another letter, a caseworker wrote: “You initially state that you took sheep and goats to graze and then you stated that you took the sheep. This is a minor inconsistency however it has been noted.”

But discrepancies in Said’s account were not minor: they were on key elements of his claim, including whether the Taliban had destroyed his house, and whether they threatened him with death if he did not spy for them.

Liz Clegg told me that the “erratic” state of Said’s interview should have been a warning sign to the authorities that he was a vulnerable adult with mental health issues, rather than a liar. “When we read his statements,” she said, “I’d be concerned about his fitness to give a statement – it was erratic, it was all over the place. Anybody who’s rocked up on a mission to con the Home Office would never make a statement like that.”

Leonie Hirst, a barrister who specialises in human rights and deportation cases, said that an asylum seeker who has been through traumatic events and may have PTSD “is going to find it very difficult to give an account that is rational, coherent; what you get is a disjointed account. Trauma makes it difficult for people to tell their experience in a linear way, and that’s often something relied on by the Home Office to determine credibility.”

Said’s asylum claim was, unsurprisingly, rejected.

On the last Saturday of February 2017, days before the Guardian was due to release a film about Said and Wali Khan, Kelly called me in a flap. He had been at Said’s flat and found a letter from the Home Office refusing his asylum application. It had been sent in late November, two weeks after Said’s disastrous interview. But it had been sitting, unread, on the floor of the apartment for three months, because Said could not yet recognise his name written in English. It was a devastating blow. Said had also missed the two-week window to appeal. Frantic efforts by Kelly and Clegg meant Said was able to submit the paperwork for an out-of-time appeal, and find a solicitor to represent him.

Said’s case is not a Home Office horror story: his caseworker was not incompetent or insensitive during his interview, and his case was dealt with in a timely manner. But what his case does show is that the asylum system requires someone to be at the top of their game to navigate it. Said – illiterate, traumatised, grief-stricken – was thrown into a bewildering system and floundered. It was only because he had two dogged, passionate advocates in Liz Clegg and Philip Kelly that he got his appeal in, that he found a solicitor, and that he even made it to his substantive interview in the first place.

“The thing with Said Ghullam is he’s so broken, he’s not able to take charge,” said Clegg. “He is terrified of what’s happening, but also, with the guilt of losing his wife and children, he’s broken … and if it wasn’t for the likes of Philip who volunteer and bother to check in on people, our system would be spitting this man out.”

Last June, I visited Said and Wali Khan and shared an evening meal with them as Said broke his Ramadan fast. Every other time I had visited, Said had been dressed in western clothing, but today he wore a shalwar kameez of loose, khaki cotton and a red velvet cap.

Facebook Twitter Pinterest Said and Wali Khan breaking fast at the end of the day in Derby in June last year. Photograph: Christopher Thomond/The Guardian

Ramadan is traditionally a time when the community comes together: people visit one another, often dropping in unannounced. Iftar meals – eaten when the sun has set, which on that day, painfully for Said, was not until 9.35pm – are bountiful and social. But Said and Wali Khan had been marking the season alone. “When a refugee or a poor person is upset, where can he go to celebrate?” said Said. It is too painful, he said, to be with others, because he was consumed with thoughts of his missing family. “I’m alone, plus I’m living with the uncertainty of my family. Not just alone, but missing my loved ones.”

He dreaded having to talk about his asylum case. Early in their time in Derby, Said and Wali Khan had been regular visitors to a nearby Afghan mosque that attracts around 300 people to its Friday prayers. Wali Khan went there every day for after-school Qur’an classes. But by this point, Said had largely stopped going. “I don’t like to go when I don’t have any good news,” he said. “The first question after ‘Hello’ is ‘How are you? What’s happening with your case?’ It’s out of kindness, but I don’t want to be reminded about it.”

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Said had been given an appeal date for August, but that would later be adjourned twice – rescheduled first for December, and then, just days before that hearing, adjourned again to 6 April this year. At this point it had been almost two years since he had been separated from his family. He couldn’t understand why the process of securing refugee status – and with it the travel documentation that would allow him to go looking for his wife and other children – was moving so slowly.

“I have a sense of hopelessness. It started in the camp in Calais, but got worse when I came here,” he said. What made it worse? “This feeling of statelessness.”

In Afghanistan, Said worked as a farmer. “I used to grow melons on my farmland: they were called Qandak and Dilwayran and they were very sweet,” he said as we walked past a large display of melons at a fruit shop in Derby in August. “In Afghanistan, melons are very sweet … these are not that good.”

He described his life in Afghanistan as a simple one: he would farm during the day – onions, potatoes and chickens, as well as melons. “I had a comfortable life there. I had a car, and in the evening I had a home to go to where I was welcomed by my children,” he said. “The best memories were of us all going to the market together, or when I got home from work. I was surrounded by my kids; it was so special and comforting.”

In his isolation and anxiety, Said was becoming depressed. Aslam, the shop owner who helped Said translate his mail, attends the same mosque that Said did. He said the mosque had embraced Said and Wali Khan – even telling Said they would waive fees for Wali Khan’s Qur’an classes – but that Said was always a bit of a loner there. “We have some people who don’t like to sit with anyone, or they want to be alone all the time,” Aslam told me in April. “He was one of those guys.”

As Said gradually stopped going to the mosque, he also distanced himself from Aslam. “Slowly, slowly he wasn’t coming to me, and I don’t know why.” This might have been because Said resented the fact that Aslam had been telling him he needed to take better care of Wali Khan, who was starting to get in trouble at school.

“He was older than me. I told him: ‘I shouldn’t tell you this, you know everything better than me, but this is your child.’ He never told Wali Khan what to do or what not to do, and he was leaving him alone. Also sometimes [Wali Khan] didn’t respect his dad … Said never looked after his son in a way we should look after our children.”

In many ways, Wali Khan had been thriving in Derby. Everyone I spoke to who knew him remarked on how bright he was, how he had caught up at school, how well his English was coming along. He was cheeky, wanted to be a doctor, spoke English impressively, as well as some French and Urdu, and his native Pashto. He loved football and was – by his own telling – an excellent striker.

In August, Wali Khan said that although he thought about his mother every day, details about her were starting to slip from him. His feelings about being in the UK were complicated; he loved England, but when I asked him if he wanted to stay, he said: “[If] my mum is here, yeah, but [if] no, I want to go back. I want to live with my mum and dad, my sisters, I want to go with my family.” I asked how he would feel if his father was deported but he was allowed to stay in the UK. “I will cry after my dad if they send him back,” he said, “or I will run after him.”

During my visits, I often noted Wali Khan’s tender interactions with his father. Because Wali Khan spoke reasonable English, he had been his father’s interpreter throughout their time in the country. The first time I met them, there was a problem with one of their radiators and it was Wali Khan, then officially 10 – but perhaps only eight – who called G4S and reported the problem.

Wali Khan was becoming increasingly frustrated that his father was not learning English, and told Kelly he was going to stop speaking Pashto at home to encourage Said to practise. When we first met Said in February last year, he told us he regularly went to the free English classes run by the charity that Kelly and his wife, Marian Regan, volunteer with. But when we went to the class to film him, it was clear Said had never been before.

Kelly and Regan had become worried about Wali Khan’s behaviour, and Said’s apparent disengagement. Last summer, Regan had noticed that Wali Khan was going out with a group of older children. She had started taking early-evening walks through the local parks, where she would often find Wali Khan and escort him home.

“He was starting to pick fights,” Kelly told me. “He was taking on people twice his size. He wanted to be king of the playground.”

“But the majority of the time he was still good, he was still engaged,” said Regan.

“He was a great kid,” said Kelly.

Facebook Twitter Pinterest Said and Wali Khan in Derby last June. Photograph: Christopher Thomond/The Guardian

Said said he found his role as a sole parent, as well as the expectations placed on him by the school and social services, utterly bewildering. “Here, I’m a both mother and father,” he said in August. “Now I appreciate how my wife took care of all the children’s needs. But [in Afghanistan] the father is always free and not really connected to these things much.”

Wali Khan’s school, whose staff did not wish to comment for this article, had a policy that if a child was not collected by a certain time, they would call social services. But on days when Said didn’t turn up, before placing a call to social services, they would ring Kelly. He would leave work, drive to Said’s house, and make him go to the school to collect Wali Khan. Said was often asleep when Kelly arrived at the house. Kelly often got frustrated with the fact Said spent so much of the day asleep, which Said said was due to crippling headaches and depression. Said’s solicitors tried to get a diagnosis of depression; if they could show he would not get the care he needed in Kabul, he might be given leave to remain on humanitarian grounds. But delays in getting a doctor’s appointment led to Said’s appeals being further adjourned, and the waiting only increased his despair.

All this led to social services becoming involved. Regan and Kelly said there were no discussions about removing Wali Khan from Said’s care, just of putting in additional support to help Said take care of him. But later Kelly wondered if their involvement, and the fear that they might take away his son – his last remaining family member – might have “spooked him”.

After Kelly left the deserted flat on that rainy February afternoon, he called Wali Khan’s mobile repeatedly. “Eventually he picked up, and he was kind of subdued, he wasn’t his normal self,” Kelly said. Wali Khan and Said had taken the train to London, where they had said farewell to a relative, and then caught a boat to France. Neither had passports, so they had to leave the country illegally. Kelly recalled the conversation: “‘My dad says we’re going to go home and find our family and then we’re all coming back,’ Wali Khan said. ‘It’s really difficult to do that,’ I said, and he says yes, he knows. I asked: ‘Did you want to leave England?’ And he goes: ‘no’. It’s super sad, really,” said Kelly.

Kelly was devastated – angry at himself, angry at Said, terrified for Wali Khan, whom he worried might try to make his own way back to England and end up at the mercy of traffickers. For a while, Kelly and Regan hoped the police might find Wali Khan and bring him back, but eventually the police stopped their investigation, saying it was not a missing-persons case, since Wali Khan, who kept texting his friends pictures of himself and was with his dad, was clearly not missing.

The fact that they left just weeks before their appeal tribunal perplexed everyone who knew them. They were so close, why not wait a little longer? Mohammed (not his real name) is an Afghan asylum seeker who met Said and Wali Khan in Calais and stayed in touch with them in the UK. Mohammed knew Said was thinking of leaving the country – he had been threatening it since he was refused asylum in February last year. “He told me: ‘I want to leave this country because they give me no chance, everything takes too long, they’re never going to accept me and give me papers … the government says I am lying. No future for me, no future for Wali Khan. I want to go and find my family,’” Mohammed told me.

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When the appeal hearing was delayed from August until December, and then until April, Said lost hope. He told Mohammed: “I don’t trust them. Maybe they are just joking with me, and just wasting my time.”

After he and his son had reached France, Said approached the authorities and signed up for the country’s voluntary assisted returns programme, which flies home those not legally in France. On 29 March, Said and Wali Khan flew back to Kabul.

Mohammed asked them why they had not signed up for the equivalent programme in the UK – they could have flown straight to Kabul from the UK, and might even have been given some money to help them settle there. Mohammed reported that Said told him he wanted nothing more to do with the British system: “Because the government refused me and don’t trust me – that’s why I’ll deport myself from France.”

Mohammed has spoken to Said and Wali Khan a few times since they returned to Kabul. “Wali Khan said: ‘I’m not happy. No school, nothing,’” said Mohammed. “I asked his father what’s going on – will you put Wali Khan in school? He said: ‘No, I need to find my family, and if we find them I will send him to school.’”

Said plans to search for his family in Iran, Turkey and Pakistan. If he finds them, he does not plan to return to Afghanistan, because of the danger there. In the first three months of 2018, there were 763 conflict-related civilian deaths across the country, and at least 57 people were killed in an explosion at a voter registration centre in Kabul in late April. But nor does Said want to return to Europe, for the simple reason, according to Mohammed, that “[On the way to] Europe he lost his family.”

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“Now I am here, I thought they would give me a passport,” he told me in February last year. “I’m now waiting for a document so I can go to Turkey and look for them. If I can’t find them, I’ll go to Iran. Apart from this, what can I do? It is one year now since I lost my children. I don’t know whether they are in Iran or Turkey, whether they are alive or dead.”

A year after we had that first conversation, Said decided that the British system had taken too long. Rather than wait any longer – even just seven weeks to make it to his appeal – he left, smuggling himself out of the country, just as he had smuggled himself in.

The last time Mohammed spoke to Said, he and Wali Khan were preparing to leave Kabul and travel to Iran and Turkey, retracing the steps of their fateful journey almost three years ago. This time, they go not in search of a better, safer life in Europe, but to find the family they lost on their way there.

The new arrivals: click here for more from this project

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