Ben Aaronovitch & Andrew Cartmel 
Rivers of London [PDF ebook] 
Water Weed #4

A cunning and ruthless Queenpin of crime, known only as the Hoodette, is ruling London’s waterways, distributing a powerful, magically-produced drug called werelight weed. Her dealers are terrified of her, and that’s because the Hoodette is unafraid to get her hands dirty, as both goblin girl Lana Blanding and posh dealer Reuel Mc Beene-Smith have discovered — the hard way.Having apprehended two of her henchmen, Detective Constable Peter Grant and DCI Thomas Nightingale are getting ever closer to uncovering the Hoodette’s identity and the source of the drug. With the pressure mounting, the Hoodette knows she needs to tie up loose ends to get the police off her track. Now, her already dirty-hands are about to become positively bloodsoaked.