Exactly 100 years ago, Albert Einstein grappled with the implications of his revolutionary Special Theory of Relativity and came to a startling conclusion: mass and energy are one, related by the formula E = mc2. Among Einstein's ideas, E = mc2 is by far the most famous. Yet how many people know what it really means? In a thought-provoking and engrossing documentary, Einstein's Big Idea illuminates this deceptively simple formula by unrevealing the story of how it came to be.