We built the world around us with horsepower. But what is it that makes humans and horses so perfect for each other? The three-part series Equus takes viewers on an epic journey across three continents and back in time to the mysterious beginnings of the horse-human relationship. In Episode 1, we go back 45 million years to meet a tiny, forest roaming creature that led to all horses today. We also visit some of the fastest, and most valuable, horses on Earth, and learn how elastic energy and a bizarre ability to breath-hold make horses some of the fastest land-runners in nature. Join host Niobe Thompson, anthropologist turned filmmaker and creator of the award-winning series The Great Human Odyssey.