For those fans of multi-million year time travel into the past who have been disappointed with the FOX ‘Terra Nova’ show, I offer a good alternative. A four-books series called The Saga of Pliocene Exile features time travel to six million years ago. The series was written by Julian May and was first published in 1981. It includes the following books in chronological order of publication: ‘The Many-Colored Land’, ‘The Golden Torc’, ‘The Nonborn King’, and ‘The Adversary’. The voyagers encounter an alien race called the Tanu who have occupied part of the planet and enslave some of the humans using advanced mind control technology.
Groups of humans travel to the Pliocene time gateway to escape The Galactic Mileu, a seeming utopia where humans have developed metapsychic powers that allow for manipulation of matter and energy. Not everyone is happy with the utopia, and some decide to make a new life in the past. The time gateway only allows practical travel into the past. Travel forward in time from the Pliocene era ages the objects millions of years.
The Galactic Mileu forbids any humans with operant metapsychic powers from travelling back into the past. However, the Tanu have developed collars known as torcs that bring the human latent metapsychic powers into full operancy. Grey torcs are for basic slavery and are generally pain/pleasure devices used for non-metapsychic menial labor. Silver torcs are given to humans that show significant metapsychic power, but the Tanu maintain firm control over the human minds. Gold torcs are only given to humans who the Tanu trust. They allow for more freedom and are typically worn by the most powerful human metapsychics.
The Tanu are beautiful and graceful humanoids who are comparable to elves in fantasy literature. There is a second alien race occupying Earth called the Firvulag who are less attractive and the tallest ones are like ogres. Both alien races are frequently at war with each other. Partly because both races have a sense of honor in combat, they fight with more traditional equipment such as swords and armor. Destructive metapsychic powers are used as well, though since the powers of each warrior are generally known beforehand, there is no arms race like there can be during higher technology warfare.
While the four-book series is science fiction, it contains fantasy tropes, particularly with the appearance and traditional behavior of the aliens. However, Klingons in Stark Trek eventually became like orcs or goblins, so SF occasionally borrows from fantasy themes in order to increase the level of drama or conflict. Some would argue that advanced mental powers are more fantasy than science fiction, and yet this saga portrays mental powers in a more realistic way than most fictional works.