Everyone can run. Whether it is a jog around the park on a Sunday morning, or lining up with 40,000 other people at the start of the London Marathon, all it requires is a pair of trainers and the open road. But where does that road lead and why do we run at all? Robin Harvie ran his first marathon after a bet, but it wasn't until he had ventured 6,000 miles into the extreme world of ultra-distance running to the start line of the oldest and toughest footrace on earth, that he found an answer. As a hobby turned into a 120-mile-a-week obsession, so a way out of his daily routine evolved into a journey to discover who he was and what he was really made of. Through the scorching heat of the desert and into the darkest hours of the morning, reveals the beating heart of the brutal and profoundly intoxicating experience of running. If you have ever wondered what makes you lace up your trainers, and why you keep coming back for more, this is your story too.