I was ferreting about in a very dark corner of a shelf at the library when I came across a book I didn’t even know existed. It was Beau Geste (by Christopher Wren), and having seen the movie I read it with great relish.
It was very good. It had such things as desert sands of Africa, the French Foreign Legion, battles, etc. And all was well seasoned with mystery and adventure. Plenty of good characters were afoot (good as in interesting) as well.
And I’ve also seen the movie, which goes by the same name, and that was also good. Well, I hope you enjoy it!