There are currently nine main Slow Horses/Slough House novels in Mick Herron’s series, plus several shorter companion works (novellas and stories).

Quick Scoop

Here’s how it breaks down:

  • Main Slough House novels: 9 in total so far, running from the first book Slow Horses up to the latest installment mentioned as newly released and titled Clown Town.
  • Novellas and shorter works: at least 4 notable novellas are tied directly to the series world – The List (2015), The Marylebone Drop (2018), The Catch (2020), and Standing by the Wall (2022).
  • Extra/adjacent books: there are also Slough House–adjacent titles like The Secret Hours , which link into the same universe but are not numbered as main-series entries.

In forum discussions, readers often talk about “eight books plus extras,” but publishing news and more recent coverage confirm a ninth main novel, with more books expected rather than the series being finished.

Information gathered from public forums or data available on the internet and portrayed here.