“That isn’t possible.” That’s what I thought when I first heard about Rob Young’s challenge. I mean, who on earth can run a marathon everyday for a year? Curious, I arranged to meet Rob for on one of his early morning marathons around Richmond Park. As we circled its leafy expanse, Rob told me about his back-story – one that, in many ways, was just as difficult and remarkable as the challenge he was taking on.

As a child, Rob suffered terrible abuse at the hands of his father. Years in foster homes followed, resulting in a childhood that Rob said he “survived rather than lived”. Yet, despite all this, he was one of the most positive men I’d met. Somehow, these experiences had created in him an inner strength – one that allowed him could carry on where others fell apart. Maybe he could complete this challenge, after all.

Rob also spoke passionately about his charities – NSPCC, Dreams Come True and GOSH – for whom he was hoping to raise £200,000. His motivation was obvious: he didn’t want other children to suffer in the way that he had.

Later that afternoon, I received an email from my friend George Bull. He’d just seen a film called The Runners. ‘It makes you want to create something honest, doesn’t it?’ he wrote. It did, and I knew just the story.

So we bought a bike trailer and convinced filmmaker Ross McClure that sitting in it with his beloved camera was a completely safe and sensible idea. We took it on a training run round Richmond Park. The trailer was heavy and the hills were steep, but Ross and his camera survived. We were good to go.

Then disaster struck. Rob’s left leg had finally succumb to the strains of daily marathon running. He was under strict doctor’s orders: no running for two months. So that was that, then: the end of the film and, presumably, the end of the challenge.

Not quite. Rob healed quicker than anyone could have imagined and set himself a new task: to run 400 marathons in a year – shattering multiple world records in the process. We dusted off the trailer and headed back to Richmond Park to film him in action.

Rob turned up in his usual garb – vest, kilt and trainers – looking a little tired. “I ran three marathons yesterday,” he said. But once he got going, it was the same old Rob: never slowing, never complaining; always honest, always open. “I don’t know if I can do it,” he confessed, “but I just want to show people that something is possible”.

What Rob told us that morning was simultaneously harrowing, uplifting and, ultimately, life-affirming. He is an infectious character. And we were glad to have gotten out of bed at 4:30am to be watching the sun come up with someone who had decided so wholeheartedly not to let worst experiences of his life define him – who had, instead, turned them into his greatest strength.

As we shot Rob on the last stretch through the park, we realised that this wasn’t really a story about running at all. Rather, it was one about freewill and self-determination: everyone’s right to choose a different path, wherever that may lead.

Watch the film.

Rob’s website.