Saga of Pliocene Exile

The Saga of Pliocene Exile (or the Saga of the Exiles) is a series of science / speculative fiction books by Julian May, first published in the early 1980s. It consists of four books: The Many Colored Land, The Golden Torc, The Nonborn King and The Adversary.

At the start of the story the Strait of Gibraltar is closed and the Mediterranean Sea is dry and empty. The Many Colored Land and The Golden Torc are set in Europe just before and during the rupture at Gibraltar. The rupture and the rapid filling of the Mediterranean form a Wagnerian climax to The Golden Torc, in which aliens and time-traveling humans are caught up in this cataclysm.

The Saga of Pliocene Exile (known as the Saga of the Exiles in some markets) is a narrative surrounding the adventures of a group of late 21st and early 22nd century misfits/outcasts who travel through a one-way time-gate to Earth's Pliocene epoch, in the hopes of finding a simple utopia where they can escape the complexity and politics of the modern post-intervention intergalactic society.

However, the reality the travelers find in Pliocene Europe is far removed from their utopian dreams. The time-travelers of group green arrive to discover the Pliocene is already inhabited by a dimorphic race of aliens ('exotics'), the Tanu and the Firvulag. The exotics, who have fled their home galaxy because of religious persecution, were marooned on Pliocene Earth when their "living" ship crashed on earth.

The Tanu and Firvulag exotics have metapsychic powers and are extremely long-lived. The Tanu use a torc-like device to bring their wide variety of latent metapsychic abilities into a partial operancy, while the Firvulag are naturally operant metapsychics - who have a limited range of abilities compared to the Tanu. The earth was selected as a new home for the exotics because the earth and its primitive Pliocene hominids were the most compatible to the Tanu/Firvulag homeworld. Over time, both the Tanu and Firvulag races have difficulty reproducing on Earth due to the higher levels of terrestrial and solar radiation relative to their homeworld. When the time-traveling humans started to arrive in the Pliocene, the Tanu enslaved many of the humans in an effort to overcome this problem, interbreeding with healthy female humans with latent metapsychic abilities and incorporating the humans into their Pliocene society. The Firvulag exotics are, in the main, a more robust than the Tanu and are less affected by the higher levels of radiation on earth. The Firvulag choose to not interbreed with humans and disagree with the Tanu's decision to integrate humans into their society, preferring to preserve the traditions of their homeworld.

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