Ben Aaronovitch's "Rivers of London" series.
1st book took me two goes to get into properly - but I think that's because I was told "if you like Pratchett, you'll like this" so I was going in with completely the wrong mindset.
It's a murder-mystery / police procedural with heavy folkloric and paranormal elements, with more snarky humour being injected as he gets into his stride as an author. I'm loving it now that I could approach it on its own merits, and just about to start book 5