For more than a century, scientists have raced to unravel the human family tree and have grappled with its complications. Now, with an astonishing new discovery, everything we thought we knew about primate origins could change. Lying inside a high-security vault, deep within the heart of one of the world's leading natural history museums, is the scientific find of a lifetime - a perfectly fossilized early primate, older than the previously most famous primate fossil, Lucy, by forty-four million years.