Brax Booker, an Olympic swordsman, who's trained in various arts with the mysterious Mr. Rimbauld, finds himself transported to another universe, to a world where he has to use all his skills and mental powers (which are now greatly enhanced) to help the people there fight off their great enemies. There's a princess, of course, and monsters. There's swordplay and derring-do aplenty, and it all moves at a great pulp pace. If you're looking for character development and introspection, look elsewhere. This is sheer storytelling for the fun of it.
There are a couple of little glitches along the way, but if you're looking for pure entertainment, this more than fills the bill. Bring on the sequel!