This is not high-end Turtledove of the "Worldwar" or "Guns of the South" level. Really, the Fox books are more like Heinlein's celebrated junior novels in some ways (though they have sex). The Fox theme is an extended and entertaining study of the abundant benefits of clear thinking and the ability to be self-critical. Adults will enjoy these books -- they're not kiddie novels -- but they have the same Heinleinian themes of competence and moral responsibility. My only caveat: this is two previously published books under one cover. (Prince of the North and Werenight). That's a good deal if you haven't read them, but be sure. I've been burned so many times by repackaged SF stuff that I feel such a warning is in order!