Pierre Fresnay plays the title role of a dedicated man, living in the south of France in the 19th-century and somewhat ahead of his time. Fabre ekes out a meager existence for his huge family as a mathematics instructor who studies insects. Recognition of his work, both in the field of entomology and as it related to man's behavior, came slowly over a 50-year period that showed him that man alone possesses a soul and free will.