"I was sitting in the middle in the back seat in the car and the bullet hit me with such force that I shot forward and my head hit where the handbrake was.
"I fell back and knew I had been shot. I had no feeling in my leg. I could feel blood running down my back - I was in trouble.
"That was it. Instant total paralysis."
Johnboy Smith was just 16 years old when his life changed in a split second.
But out of adversity has come a new challenge in the shape of wheelchair racing and now he wants to inspire others as he chases Paralympic success.
Born into a Traveller background and living in Kent, in 2006 Smith was a keen amateur boxer and training to be a plumber and plasterer. One day, while out with friends, he stumbled on, as he describes it, "the wrong farm at the wrong time" and was shot by a farmer who, wrongly, believed they were poachers.
The bullet was fired from a rifle at the estate car in which Smith and his friends were travelling. It went through the car tailgate, through a dog in the boot and through the car seat, into his spine.
"We were about 20 miles and 40 minutes away from the hospital," he recalls. "On the way, I was coughing up blood and couldn't breathe. I wanted to say goodbye to my mum and that was what got me to the hospital.
"I remember everything until I got to the hospital and I blacked out then."
As well as the paralysis, Smith had a collapsed lung, ruptured spleen and a perforated bowel and was in intensive care for a week.
In 2010, the man who fired the shot was convicted at Maidstone Crown Court after pleading guilty to inflicting grievous bodily harm, while another man was also convicted of the same offence.
In hospital, Smith was told he would be a wheelchair user for the rest of his life - something he found hard to comprehend and accept.
After the shock wore off, and with the support of his friends and family and the wider Traveller community, he started rehab at Stoke Mandeville Hospital and faced a different future.
"Very early on at Stoke Mandeville, I was lying in bed and just thinking what was I going to do now," he says.
"If I didn't pull myself together, I didn't know what the situation would do to my parents, not just me.
"My mother was pushing me around the hospital. As a 16-year-old, I didn't want her to have to do that and I wanted some dignity, so that inspired me to be better and stronger mentally and physically.
"I knew I had to build some upper body strength and started lifting weights and it all started from there."
Smith began by doing some wheelchair body building and powerlifting. Watching the London Paralympics in 2012 made him crave the bigger stage.
He moved to athletics and started to compete in the seated throw events in his category. But at an event in Berlin in 2014, he saw wheelchair racing up close and knew then that he wanted a piece of the action.
After some persuasion from his father and an internet search for "Where does David Weir train?", he ended up at the Weir Archer Academy, set up by the six-time Paralympic champion and his long-time coach Jenny Archer.
Archer, known for her no-nonsense attitude, took one look at Smith, who at that point had the physique of a thrower rather than a wheelchair racer, and bluntly told him to come back when he had lost four stone.
Six months later, a slimmed-down Smith returned to Archer, who initially didn't recognise the transformed young man in front of her, and his wheelchair racing career started.
The 29-year-old made a big impact on his international debut, winning silver when representing England in the T54 marathon at last year's Commonwealth Games in Australia.
This year, in Sunday's London Marathon, just weeks after wife Kerri gave birth to twin daughters, he wants to better his 11th place from 2018 in a race which doubles as the World Para-athletics Championships.
Weir will be going in as favourite to land a record ninth London title in his 20th consecutive time around the streets of the capital but while old foe Marcel Hug from Switzerland will challenge again, the rising star on the block is American Daniel Romanchuk.
The 20-year-old won in Chicago and New York last winter before triumphing in Boston two weeks ago.
Australian Madison de Rozario defends her women's title but four-time champion Tatyana McFadden from the USA and Boston champion Manuela Schar from Switzerland will push her all the way.
Smith wants to show what he can do with just over a year to go to his main target - the marathon at the Tokyo Paralympics where he wants to win gold.
"The T54 category is so competitive. I can turn anything into a competition and this suits me well," he says.
"I could never have imagined me doing anything like this. I am just a local lad from Kent. Whatever I do I put my heart and soul into it. It has just come naturally to me.
"My motivation is that you can have the worst news in the world, but there is life after disability and tragedy.
"If someone, whether they are from the Traveller community or not, comes to me and says I am the reason they are getting out of bed, then I have done my job. I want to inspire people. It's not about being an elite athlete - just be better than yesterday."
Eight-times London Marathon champion David Weir on Johnboy Smith
"He did some throwing events, I think, before wheelchair racing. I think his mindset was 'this is a bit boring for me, I need to challenge my mind and try a new sport'.
"When I first met him I knew he had that attitude and that mentality to do well in the sport because in first impressions you know with someone. He's got that mentality that he wants to be successful in the sport.
"He's had some good races in a short space of time - Berlin last year he got third and New York in 2017 as well. You know, he's an up and coming athlete. You have dips in the season and you have ups, because that's the way it goes when you're still learning about the sport and training and stuff like that. But he's learning and he's listening and he's doing really well. I'm proud that he's come through our academy. It's a bright future for him in the sport."
David Weir was talking to BBC World Service's Ed Harry