This is a riveting and complex police thriller, with multiple suspects for several different but possibly connected killings with dissimilar MO's. It's interesting that there re so many candidates for each killing - it makes everything a little more challenging.
Russell holds all the plot strands together masterfully and makes each incident suspenseful and intriguing. Despite the complexity, the expositions at intervals throughout the novel seem pretty natural and unforced and allow the reader to catch up and summarise things when there is a lot going on. Hamburg itself is a character in the story, and this novel is full of atmosphere.
There's also an interesting backstory about former Stasi assassins trying to exist in the new post-reunification world, as well as an insight into the psycholgy of female killers. And Fabel is a sympathetic character you respect and root for.
This is the first book in the Hamburg/Fabel series that I've read - I think it's the fifth, chronologically, and it's made me want to read the others as soon as I can. Best read of the year for me. Don't miss it.