In this elegantly-written and engaging book, John Derbyshire gives expert form to the beauty and mystery of the most abstract of mathematical disciplines: algebra. Derbyshire brings to life the cast of extraordinary and bold historical characters each of whom, though the centuries and across the world, played a role in its genesis: the ancient father of algebra, Diophantus; the dashing, romantic Evariste Galois, who developed algebra to ever higher levels of abstraction, fell in unrequited love and died, age twenty, in a pistol-duel at dawn; and the dazzling and tragic Hypatia, probably the only mathematician in history to be skinned alive by an angry mob. Far from being dry or irrelevant pursuits, these adventures in algebra heralded nothing less than a revolution. Algebraists not only gave birth to a new way of thinking about and understand basic numeric concepts, but they also changed forever our very perception of the world around us.