Lieutenant of the French forces engaged in Mali, David Faber is seriously burned during the explosion of his armored vehicle. Repatriated to France for intensive care, he must begin a long convalescence, under the worried but devoted gaze of his sister Jeanne. They meet again in the family house in the Alps, between mountains, lake and forests. Jeanne tries to reconnect her brother with the past, but David, who suffers from amnesia after the accident, does not seem to be interested in reconciling with the man he used to be.
Albert Spaggiari is arrested in Nice and brought to a judge's office for interrogation, but he escapes to South America where he meets a journalist who is investigating the event.
En 1870, el joven médico escocés Jamie Dodd y la aventurera Elena Van Den Ende viajan al corazón de la inexplorada África Ecuatorial en busca de los orígenes de la humanidad. Regresan a Edimburgo con dos pigmeos que, considerados como los 'eslabones perdidos' entre el hombre y el simio, serán expuestos en el zoo como animales. Jamie emprenderá entonces una cruzada para protegerlos, asegurando que su inteligencia y sensibilidad son idénticas a las de cualquier ser humano. Una postura que le causará multitud de problemas.