I don't think anything by RJB is going to disappoint me, and this novel certainly didn't change that trend. I absolutely devoured this novel in two sittings. 

With The Tainted Cup, Jackson Bennett has envisioned another breathtakingly complex fantasy world for readers (although there are whiffs of the world-building from Founders - gates with specially devised keys anyone? they're different here, but nonetheless, fun little easter egg). Dinios Kol, our MC, is the dyslexic (or something akin to it) investigator who is assigned to the very odd, and seemingly banished, Ana Dolabra. 

A very strange murder (one where plants grow out of someone fairly important in the empire within a five minute span, killing them in the process) is what sets off the chain of events that take Din and Ana to another part of the empire to pursue to murderers, and investigate some identical ones, putting the outer ring of the empire at risk. What ensues is a fantastic adventure through the city, into the homes of the gentry, who wield terrifying amounts of wealth and power of course, and through dark streets. 

Absolutely loved this one, and can't wait to continue this series.