Parisian professor Stephane (Philippe Volter) is a linguist specializing in long-lost dialects. But one day he begins to hear a new one, in the form of radio transmissions: strange orders, apparently coming from some extraterrestrial entity. Stephane questions his own sanity, as does his friend Fabien (Christophe Bourseiller) and his fiancée, Brigitte (Nathalie Roussel), but when the transmissions foretell actual disasters, Stephane begins to think the fate of the planet could rest in his hands.