The real duration of the film is barely one second. The time that an idea takes to be born in our mind. The time that a fleeting hallucination lasts. This hallucination is that of Neanderthal man who thinks he sees, at the moment his mate was giving birth, a baby from the modern world, erasing for a fleeting second the slow evolution of the species. Immediately after, the mind of the primitive man goes on a imaginary time travel trip that takes him to... 1960. The father tries to get in touch with his son, reincarnated as a 40-year old man, an ordinary man... or almost.