In a dark, cramped apartment on Rue d'Argel, in the heart of Paris, Eugène Schueller sits at the stove. He lights one and, concentrating hard, heats a saucepan. It contains a thick paste that he stirs carefully while adding the final touches of a thousand ingredients. His intuition tells him that this time, yes, he's going to get it right. It's 1907, and after weeks of puzzlement, he feels he's about to stumble upon the ideal formula: a product capable of dyeing hair a uniform, shiny shade without causing irritation or unpleasant odors. He takes a spatula and, using surgical powder, deposits a small amount of the mixture onto a strand of hair that has been waiting on his desk for days. It only takes a few seconds to confirm: he's just created a dye with enormous potential.