Remarkable, not to say peculiar goings-on in London, as the Investigators are visited by a stranger seeking their help - who dies before he can explain the problem. Then the police arrive, not about this body but about another one that has their address in its pocket... only it seems to be the corpse of the same person, Edward Bigsby! It only gets worse, dead Bigsbys turn up all over the place!
Introductory material lay out what is going on, which Mythos being is involved - the Investigators may even encounter him if they make too much of a mess of things! - and a strange mechanism that is causing the duplications to occur. It also presents the Spine of the adventure, and then we're off...
Much of the action is set in Soho, a part of London that was very Bohemian in the 1930s (and still is, for that matter). There's a fair bit of background to help you bring it to life for your group. It's a bustling place with a varied population, with artists and poets rubbing shoulders with drug dealers and card sharps. People from all over the world are found here: Irish, Australians and Chinese to name but a few. There are gangs and criminals and ladies of negotiable affection... plenty going on even before the adventure starts.
As for the action, there's a cult to investigate, a Chinese restaurant crawling with triads to visit as well as a museum ... and of course most Investigators will want to find the man who sent Bigsby to them in the first place. Plenty of action and interaction to be had in what is a fun and busy scenario. And just when the Investigators think they are done... the police turn up again.
It's an inventive and neat adventure with a lot going on, yet well-constructed. It would probably make quite a good film. Notes at the end suggest ways of linking it in to a Bookhounds of London campaign if you are running one, but it works just as well if the Investigators - or at least one of them - are based in London for any other reason. Just watch out for green doors!