But why on earth, on a lost island in the Pacific, strange birds show blue feet that are found nowhere else? By what whimsical, capricious and mischievous path, the strangest forms of life have found their way to the Galapagos archipelago? On land and under the surface of the ocean, in the course of a playful and learned investigation, L’Ile aux Fous tells the great story of life, that of an extraordinary machinery made of perseverance, resilience but also of sympathetic errors which are the true engine of evolution.