“Slough House” by Mick Herron

Finished this, the second to last book in the boxed set that we have, about a week ago. Then discovered just now: a ninth book in the series (not in the boxed set) was published last year, AND there is a handful of novellas that fit in tangentially. Well, you know me--I guess I'll have to read them too . . . 

While I still enjoyed reading Slough House, I also found it a bit meh. I can see why they combined this one with Joe Country to make Season 6 of Slow Horses.  

This is the one where the Russians get ahold of an old Slough House staff list and use it as a prompt for revenge. It ends with a cliffhanger which I fear will make my daughter (formerly Bookworm Child, now Bookworm Adult) hate it and never watch Slow Horses again.