Mutants and Masterminds. Let me start by saying this is a really useful book. However, I think it has a major flaw. It's called the Supernatural Handbook, but I think Horror Handbook would be more appropriate. If you're looking for far out Ditko-inspired mysticism, you're not going to find it here. However if you want Predator, Marvel Zombies, or John Carpenter's The Thing, this book is for you. The book is divided into five chapters.
The first chapter is entitled A World of Horror and is definitely designed with GM's in mind. It discusses different styles of horror campaigns (many of which have nothing to do with the supernatural) and how to play them at various power levels. A discussion of horror through the ages is also present.
The second chapter is The Player's Guide to the Supernatural. One of the early ideas is redesigning character creation with the monstrous in mind (with complications and the like in mind). Supernatural hunting equipment and occult tech is also addressed. The book presents 7 archetypes. I have a big complaint with one. The Infected Hero is a great concept. However, except for complications, it is pretty much the same as the Speedster archetype in the core book. This is a wasted opportunity. This chapter also includes Monstrous Templates which help players and GM's create a plethora of archetypes.
Mastering Your Fears is chapter three. This is an depth discussion of horror from a game master's perspective. Different types of fears and what causes them are presented. In addition, classic horror game concepts: corruption and madness.
The fourth chapter, Misadventures in Horror is really useful. It starts with a super-handy-no-matter-the-M&M-game critter builder. It has 8 monstrous villain archetypes that are just damn creepy or cool. The Alien Trophy Hunter is the Predator! It also includes adventure/series ideas in the Clippings and Case Files section. These are all pretty interesting and contain npc stats (including deep one stats). My favourite is the Blood Cult. It's a Dracula-led organization that recruits society's elite.
The final chapter details ARCADE, which is a bump back against the night organization. Due to mystic powers, only 200 folks can know of ARCADE's existence. To me, this makes them hard to use, unless players are members. Oh yeah, and their leader's name is a Predator reference, and that makes me smile.
If you're coming for 70's Dr. Strange you're going to be disappointed, however if you want some John Constantine and BPRD, this book has you covered. Honestly, I think there's enough in this one to make it useful for all M&M game masters. It's worth the price of admission for the monstrous templates and build a critter section. You can order your copy of the Supernatural Handbook here.