As usual with Fantasy Flight Games, they produce some excellent game mastering products for their games. The GM Kit is a screen, a pregen adventure and very useful tips for building missions. The GM Kits for the Warhammer 40k line have always been pretty excellent, with a lot of useful reminders on them, but if you've seen any GM Screen before you'll know whether you want to use it or not. It has enough Deathwatch specific info that you probably wouldn't want to just stick your Dark Heresy screen on the table or somewhere. But at the end of the day it's a GM screen. The enemy for the pregen adventure is the Tau and the adventure has some pretty cool stuff like an attack by a Manta craft and a chance to use a few Space Marine vehicles, like a thunderhawk and speeder. I don't want to give a lot of the module away, but there are a few cool optional rules and a plot that make this just a bit more than "Space Marine kill a bunch of Tau and leave." The section on building missions is rather short, it isn't a like having a whole chapter in a major book from the line, but what succinct info it has is very useful. It breaks down the mission-building process into bullet points for easy digestion, tackling Location design, stocking the mission with Enemies, assigning Objectives, utilizing Assets, etc. For its brevity, it holds a ton of information and I can see myself going back to it before every adventure and consulting it quickly. If you're a Deathwatch GM, you will likely enjoy this book. However, if you are not a believer in GM screens, and if you don't really care about module adventures, the pamphlet-length mission design section may not be enough for you. Overall though this is an excellent product. FFG has yet to disappoint me with their GM-oriented products.