I read this back in the mid 80's, soon after I had finished all of [author: J.R.R. Tolkien]'s novels and [author: Stephen R. Donaldson]'s Covenant series. It so intrigued me that I read the entire four book series in a week or two. I eventually read the rest of [author: Julian May]'s works, but with less enthusiasm. The Pliocene Epic was intriguing because it was a time travel science fiction story with psi powers thrown on top. It sometimes felt like fantasy, with what seemed like magic, but you knew it was really science and mind powers behind it. It appealed to the misfits and underdogs who sought to escape a society that didn't want them and wanted to drastically conform them, with a one-way ticket back in time. But the paradise they were expecting six million years in the past was tarnished by alien tenants who used the unsuspecting humans as slaves or playthings and rarely as a privileged peer. The struggle for survival and freedom starts in this novel and continues through the other four. I haven't read this in a decade or so, but many of the images are still vivid in my memory. [author:Julian May] does an excellent job of blending good character development and thrilling plot developments.