The outer cover is a folder containing the two booklets. A bit flimsy, but it does have some good maps (additional to the map booklet) and a cutaway view of Stormhaven Mansion on the inside, along with the Paul Jaquays painting on the front showing an autogyro, looming supernatural creature and mysterious figure at the window to give you some idea of the possibilities in the setting.
More than half of the main booklet concentrates on background material, character descriptions and the location itself. The remainder consists of adventure outlines (one brief, two more detailed and several described in a paragraph or two), options for getting your PCs to Savage Island and character stats for both MSPE and the Hero System, here in its earlier Espionage! version. Most of the material is printed in dark green on light green paper, which could be an issue for some people although the contrast is reasonably good.
When it came out Stormhaven was rather more unusual than it looks today, now that we've had more than a quarter of a century of products it inspired. This is very much a setting pack, concentrating heavily on the possibilities and atmosphere provided by the location and the NPCs involved. The GM is given all sorts of options for adventures, featuring various degrees of mystery, technology and even supernatural involvement. The adventures and adventure suggestions include Dracula, spies, the KGB, a mysterious disease, god summoning and a quest to clear the family name, so there's no shortage of things to do, but for most of these the GM should be prepared to do a bit of work: if you want more linear, step-by-step scenario plottings then you may be disappointed apart from the longer adventure descriptions. Throughout the product you'll find mind evidence of Mike Stackpole's love for the source material, including little in-jokes such as certain character names. It's a deep and rewarding setting if you're happy with the sort of mysterious island, family politics, high-tech espionage and gleefully pulpy action it offers, but it does certainly require that the GM spend time to absorb the details in order to make the most of it. One more example of why Mercenaries, Spies & Private Eyes is such a criminally overlooked game.