I was a big fan of the designer's previous game Brindlewood Bay, and have been anticipating this one. So far I've run two sessions and am really excited for more.
This game does a great job of evoking a spooky Victorian atmosphere - with 50 atmospheric 'unscenes', sets of notable Moments and thematic prompts in each Threat, and playbook moves that are incredibly (sometimes horrifyingly) flavourful. The approach to presenting NPCs is incredibly efficient and lets me as GM create a compelling, diverse cast at the table with minimal preparation. I have started using this approach in my notes for other games I run and it works fantastically well.
As much as I hope I get to play a character in this game at some point, there is so much here for the GM to enjoy. The formalised play cycle (four phases - dawn, day, dusk and night) gives you a unique tool to pace the game dramatically. The way specific playbooks can trigger or unlock particular threats - the Pinkerton coming for the American, etc - is a really fun dynamic to run. The overarching campaign structure - the Mastermind - works like a special playbook, with fascinating questions and choices the GM gets to make as the game continues, and a play-to-find-out emergent narrative that drives toward a big dramatic climax. I really enjoy a lot of pbta games, but often find it hard to bring them to a satisfying conclusion, and I think this and Brindlewood Bay offer a really elegant and exciting solution to that problem.
I definitely recommend this game if the concept and tone appeal to you. Even if they don't, I think there's a lot of really useful mechanics and ideas packed in here that you can use or hack for other games.
[5 of 5 Stars!]