I really liked this actually! The author's note at the end of the book compares itself to Mexican Gothic and I'm gonna be controversial - I liked this better than Mexican Gothic.
I think the main reason I feel this way is that in half the amount of pages, I cared more about and enjoyed Alex than I did about the protagonist of Mexican Gothic. I feel like Mexican Gothic gets very overhyped honestly. The story does not overstay it's welcome, being much longer than the original source material but at the same time being less than 150 pages long. I'm genuinely excited to hear that Alex is coming back for What Feasts At Night which actually came out just a few days ago. I loved to hear that the author's note described how much they seemed to appear fully formed from the ether to fit into this story.
The whole book reads like a modern classic horror book which is a breath of fresh air from the amount of 'nothing' contemporary horror books I read. A lot of the characters were reminiscent to how I felt about the side characters in Dracula for example. Also that's a great horse, we love Hob.
The pacing is great, for a novella it doesn't dilly dally but gives great respect to building to the reveal. You can really tell that Kingfisher put a lot of time and effort into developing the fungus (I really do have a soft spot for evil myconids though often it's more that they have no conscious thought to be evil just that it just does what it does). Really offputting but cool detail was how long Madeline had actually been dead while at the same time teaching it how to communicate conventionally as humans do. Amazingly weird detail, I loved it.
House of Usher is one of my favourite Poe works so I knew (what little I knew of this book) that I would definitely enjoy this if it was done right. And it was done right with gusto. This is my first T. Kingfisher book and I can safely say that she has cultivated a fan for her writing style, evocative description, likeable characters and awesome horror concepts.