The third novel in a series can be a bit of a let down, but Robert Jackson Bennett makes this the best so far. In his beautifully imagined world which has advanced biological technology while otherwise being near-medieval we once more encounter the unlikely pair of investigator Dinios Kol and his boss, Ana Dolabra whose ability to pull together information from multiple sources to come to deductions isn’t quite human - and whose personality is abrasive to say the least. They are called in to deal with what appears to be a relatively simple murder with a clear perpetrator, but that conclusion risks political instability as the daughter of one leading family is killed by the son of another - the two lines being close to Montagues and Capulets in their hatred for each other, even though their businesses are intertwined. What gradually becomes revealed is a far more complex plot involving a horrendous biological mechanism that, at the same time, gives Bennett a chance to tell us much more ...