I'm a fan of these types of supplements that allow me to pull a character out of thin air when my mind is feeling less than creative. The book has advice, obviously, for creating interesting NPCs. Maybe more useful for me is the list after list after list of NPCs to grab at a moment's notice. There are NPCs for Fantasy, Sci-Fi, and Modern with additional indexes by trait, name, and author if you want a certain person's flair.
The categories are broken down into villains, neutrals, and allies. You get enough background, personality traits, and descriptions to really run with this. A very helpful supplement in my opinion.
[4 of 5 Stars!]