Through a series of evidences and arguments, complete with illustrations, photos, and other inserts, Temple (convincingly) leads the reader to a conclusion which, uncharacteristically of academic publications, is well summed up in a few paragraphs, perhaps two pages, revealing and solving the mystery of the Sphinx. Or, at least, it gives a very plausible explanation which is simple, elegant, and highly believable.
The book is incredibly interesting, if somewhat dry (it is, after all, academic), and though it took me many (18) months to finish, was well worth the read.