Forward Into the Future!

Our five adventurers, adults now, are together all spun on their great horses to a distant, alien planet where they meet a race of creatures that collectively have all the knowledge of the universe at their disposal. Most of their questions about their adventures are at last answered, and they meet the creatures leader, who sets them on what seems to be an impossible task. In the meantime, among other things, they are shown the imminent destruction of the planet theyre on and have a horrifying encounter with some truly evil trees.
This book is the last in the Back To series and is quite different from the others in that it is not based on real history but is pure sci-fi. It was written, like the other five, for anybody aged about ten to adult who likes stories of fantasy and adventure.