1912. Reporter and novelist Adèle Blanc-Sec travels to Egypt to find the Pharoah's personal physician, whose knowledge could save her sister, who's been in a five-year coma since a tennis accident. When Adèle returns to Paris, the intrepid young woman learns that her friend Espérandieu has been imprisoned and sentenced to death for allegedly hatching a pterodactyl egg. Undaunted, Adèle plots to help Espérandieu escape while trying to find the prehistoric bird that is now terrorizing Paris. The adventurous writer gets unexpected assistance from Andrej Sporovski, an intelligent but shy young scientist who awkwardly confesses his deep love for her.