This season wasn’t awful so much as “just okay,” but I’ve come to expect more from the show. It took my least favorite book and changed it in weird ways that didn’t feel like they fixed much. A few changes were good, but others felt like they added too much complexity to the plot or that they were trying to lend a gravitas to characters that don’t need it.

I’m surprised to be rating this higher than previous seasons, because it’s based off of one of my least favorite books in the series. I like the series more when it leans into the petty and mundane, and this book feels almost like a blockbuster spy movie with its unstoppable bad guys and conspiratorial plots.

That turns out to make for good television, though, and I thought the season finale was particularly good, in a way that raises my opinion of the whole season. I am feeling excited about this franchise and might do a reread while I wait for the fifth season to come out (not least because I’m struggling to remember the plot of the fifth book).

What an excellent series this is. The finale was more violent than I’m comfortable with, but I appreciated that it never glorified the violence; rather, it fit in nicely with the series’s habit of showing that as screwed up as the Slow Horses are, it’s the dignified leadership of this fictional MI5 who are the real monsters. Power corrupts, and all that. I’m wondering how next series will go—I have only vague recollections of the book, and what I do remember is that it’s one of the weirder ones.

I’ve been looking forward to this since the first season ended. Midway through watching the first season, I’d already begun reading the series, and I may have already finished the second book by the time I saw the trailer for the second series. This season did a great job at making use of the source material while changing and improving things as needed. It’s a fun book series, but I think it’s shaping up to be a better show.