Only days before he left hospital Jim Berry had one of those moments when suddenly he saw himself as others saw him. “I was wheeling myself along the ward on a Zimmer frame,” he says. “My right eye and about a quarter of my head were missing. Above where my eye had been I had a sort of cereal-bowl-sized crater. I thought, ‘What would my mates think of me now?’ ”

Berry, 26, a lieutenant in the Royal Irish Regiment, didn’t want to be drawn into the “downward spiral” of feeling sorry for himself, though.

“I wouldn’t allow myself to go down that path. I wouldn’t want people to pity me,” he says.

An explosion in Helmand province, in Afghanistan, 15 months ago sent a fragment of shrapnel through Berry’s right eye and into his brain, where it lodged. He was in a coma for two weeks with a 20% chance of survival.

Today he is back at work revamping his battalion’s website - as well as running his own, www.soldieringon.com and planning his wedding next year to his girlfriend, Marianne Fox.

The only indication of the severity of his injuries is a false eye. His handshake is firm, his walk determined, and he’s looking forward to celebrating a traditional Christmas at his home in Guildford, Surrey, with Marianne and his family.

Last year, when he spent Christmas at his parents’ house in Leicester, he couldn’t walk or drive - and Christmas dinner was the first meal he had eaten without special cutlery since being wounded.

“I’d been using these specially adapted knives and forks,” he says. “But I’m a bit proud. I didn’t want people thinking I was that disabled. This year, I can walk, I can drive, I can even sort of run, but I’ve been told not to because I haven’t learnt how to run properly again.”

Berry attributes his extraordinary recovery to the help he received at Headley Court, the military rehabilitation centre in Epsom, Surrey, which is being supported by this year’s Sunday Times Christmas appeal.

“When I went there after hospital I badly needed help; I couldn’t walk and I had to have a nurse with me all the time,” he says.

At the centre, which is treating scores of injured men from the conflicts in Iraq and Afghanistan, the emphasis is on getting them back into “normal” life. Berry’s treatment ranged from the practical (“buttering a piece of bread, holding a cup of tea, writing my name”) to the militarily specific.

“I can run a range controlling guys shooting at a target,” he says. “My consultant thought I’d never be able to and came to shake my hand on the day I did it.”

For all his bravery Berry is a slightly unlikely soldier. He trained and worked as a graphic designer but five years ago decided to give up his job and his “grotty, expensive flat” in London to enjoy more of what he liked best: the camaraderie of the Territorial Army.

When he decided to go for officer training at Sandhurst his father was delighted, although his mother was “a bit worried about losing me”.

After 44 weeks at Sandhurst he served in Northern Ireland - “very benign; we were offered lots of cups of tea” - and Iraq, which was “like Northern Ireland but very hot”.

After his return to the UK in 2006 Berry was made second-in-command of his company, one platoon of which was attached to 3 Para, serving in Afghanistan. “I was desperate to go,” says Berry, “Not going was like being left on the bench for a game. I also thought that the Taliban were an evil regime; I wanted to be involved in getting rid of them from Afghanistan.”

When Berry set out for Afghanistan a few weeks later, he and Marianne had been together for three years. They’d met in a bar in Guildford, where, Marianne says, she knew immediately that the young man in the cream trousers, blue shirt and tie was a cadet at nearby Sandhurst.

“That’s what they all wore on their nights out,” she smiles.

By the time Berry went to Afghanistan, he’d named Marianne, after his parents, as his next of kin. She describes her boyfriend as “very confident and determined” - qualities that were to play a crucial role in the months to come.

When Berry arrived at Camp Bastion, the main army base in Helmand province, he saw a similar desert landscape to Iraq’s but with mountains. The base was in the Sangin Valley, “a hotbed of Taliban activity”, he says.

“The people were a lot poorer than the Iraqis,” he continues. “Their houses were made of mud and straw. Apparently it’ll take 14 years for their economy to catch up even with a poor country like Bangladesh.”

On Friday September 29, 2006, Berry and his soldiers were on a task to ensure that the immediate surrounding area was free of Taliban. “I was kneeling down next to a doorway with my bayonet, about to clear the building, so I was probably quite tense,” he recalls. Then came the explosion.

Berry, in a critical condition, was rushed to the camp’s hospital by helicopter and flown to Oman.

His parents were on a flight to Italy at the time, so it was Marianne who received the knock at the door.

“I was devastated,” she says. “Obviously you watch the news and you hear about soldiers being wounded or killed in Iraq or Afghanistan, but you never think it will happen to you. As soon as I heard it was a head injury I knew it was very serious. We were told Jim might not make it.”

As his parents organised flights home, his regiment in Inverness was preparing for his funeral. “I think it would have been a decent bash,” Berry says wryly.

Marianne, herself a nurse, was profoundly shocked when he arrived for surgery at the Queen Elizabeth hospital in Selly Oak, Birmingham. “His face was very swollen and he had a huge patch over his eye,” she says. “As a nurse you’re more prepared than most, but you’re not prepared for it to happen to someone you love.”

After two weeks in a coma Berry began to regain consciousness. Seeing his father at his bedside he thought: “What’s my dad doing in Afghanistan?”

Berry couldn’t speak or do anything much for a while but he could point to letters and was eventually given a computer keyboard. Marianne says: “When I realised he knew his password and his driving licence number I thought, ‘He’s going to be okay.’ I mean, I don’t know my driving licence number!”

The next task was to remove Berry’s wounded eye. Naturally, he was worried: “I thought, ‘That’s my shooting eye. And how am I going to drive without my right eye?’ When you go from being an officer in the army to being a patient in hospital your life is very, very different.” Those in charge had limited hopes for what he might be able to do in future.

After seven weeks in hospital Berry went to Headley Court. In five months not only did he achieve almost total physical recovery - the day we meet he offers to drive me to the railway station - but he also became imbued with the renewed confidence that emanates from him today.

“I couldn’t be doing what I am today without Headley Court,” Berry says. “Their help was priceless.”

Headley Court is a publicly funded facility, but because of the operations in Iraq and Afghanistan it is being overwhelmed by casualties - so much so that some staff have been asked to move out of hospital accommodation to make way for patients.

In September a new charity, Help for Heroes, was set up, with Jeremy Clarkson and his wife Francie as patrons, to raise funds for a new gym and swimming pool complex at the centre. Readers of The Sunday Times have already been extraordinarily generous, donating nearly £450,000 of the £2.2m accrued so far.

Help for Heroes aims to raise £5m overall, which will be used to build a facility where wounded soldiers can recover in peace and privacy. “A swimming pool will be invaluable,” Berry says.

Swimming builds upper-body strength and aids recovery, but at the moment the centre has only a small hydrotherapy pool, and injured soldiers have to be bussed to the nearby public pool at Leatherhead. There have been distressing scenes, when members of the public have objected to the amputees swimming in the pool, saying they will “scare the children”.

On his first outing from Headley Court, Berry went to stay with Marianne. He hadn’t yet had his facial reconstruction and her landlady was horrified when she saw him.

“Strewth,” she said. “What happened to you?”

“I was running with scissors,” he joked.

Today Berry says: “I’m not positive about losing my eye, but my life isn’t over. Of course I have moments of ‘Why me?’. But it’s happened. Now I’m almost a little bit proud of how I lost my eye.”

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