This supplement comes in two parts: firstly an introduction to this remarkable flying steam city and secondly an adventure based there.
This brainchild of the Prince Consort and two engineering giants, Isambard Kingdom Brunel and Robert Stephenson, was commissioned in 1851 in the wake of the Great Exhibition but construction did not begin until 1864 by which all three were dead... some said it might never come to fruition yet in 1875 Her Majesty's Flying Steam City Atlantis - affectionately known as the Cog - was officially opened by the Prime Minister, Benjamin Disraeli. It floats above an artificial island, anchored by chains to the sea floor, and by all accounts is a quite remarkable place, well worth a visit.
Presented with loads of atmospheric detail, maps and more, we learn of its structures, operating practices and above all the colourful personalities to be met there. All manner of rumours and legends have already built up about the Cog and many are presented here, make of them what you will. Just reading through provides plenty of inspiration for things that might be going on here that would provide sources of adventure.
Chapter 2 is a complete adventure (just in case you haven't already come up with a few of your own...) titled 'Adventure in the Clouds' and providing an excellent dynamic introduction to the City, as the characters are assumed to be visiting for the first time. If you use the pre-generated characters provided, they all have reasons for going there, there's a (slightly cheesy) suggestion for getting any other characters to visit if their backgrounds or your own imagination fails to suggest anything better.
Set in 1880, so far the city has been kept safe from the machinations of foreign powers or other such unsavory folks. It will be up to the characters to keep it that way... even if they do not suspect it at first. The adventure comes in three Acts, beginning with their flight to the Cog and then their arrival aloft, a beautifully-atmospheric piece that should make this remarkable edifice come to life in your shared alternate reality. Fascinating people to meet, interesting things to see and do... and designed with beginning characters in mind, to enable the party to get to know each other.
Once there, events take a nasty turn quite quickly as the action hots up. A murder is just the start of it, and investigations follow thick and fast culminating in, shall we say, an explosive turn of affairs... and that too is merely a starting point. Plenty of resources for the GM to develop matters as appropriate, an exciting steam pulp frolic to start your campaign with a bang!
Appendices contain pre-generated characters and additional attributes. All in all, this provides a wonderful flavoursome introduction to the style of this game.