As the final book in this trilogy, I expected a lot more. The writing was very loose, and multiple minor plot lines bounced around rather aimlessly until they all sort of fell together at the end. It's really not Greenwood's best novel. As another reviewer stated, it was much more of a "clean-up" intended to get certain things set up for the launch of 5th Edition Forgotten Realms.
Unfortunately, very little is actually explained. Nothing new is learned about what happened to the goddess Mystra. Nothing new is revealed about the past they've had to suffer through without her. Even the blueflame magic items (artifacts?) aren't really expanded upon at all. We don't even really get any details about what the Simbul was doing, why it was so important to Mystra, or how (or even if) it had any kind of impact on Mystra. In general, I get that the Simbul was repairing rifts. But why would a fallen goddess want to expend the energy of her last remaining followers on this? Was it important to the Weave? Why did these rifts form in the first place? And if they were dumping out that many demons over the past 100+ years, why haven't the Realms been overrun? No answers, sadly.
The major villain, Manshoon, loses focus for much of the book. Interesting characters like Amarune and Arclath are totally glossed over and do nothing. Instead, there's an exceedingly clunky and lengthy diversion into the Underdark, which ultimately seemed rather pointless except to reunite Elminster with the other characters. That would have been fine, had anything meaningful or interesting happened along the way. The subplot involving the Shades of Netheril also might have been interesting if something had been said about magic changing or expanding, creating new and incredibly dangerous possibilities, or something/anything along those lines. Instead, it was presented as a rather random criminal activity, perpetrated on a distant and isolated prison.
The "wacky and bumbling cops" comedy wore thin very quickly. Is every guard in Cormyr ineffective and clumsy? The same was true for the portrayal of nobles. Yes, many nobles can be arrogant and self-serving at times, but when this is true ALL the time and no shred of intelligence is ever observed you have to wonder why the kingdom is even standing. Sadly, it gave the strong impression that without Elminster, Vangerdahast, Storm, and a few other immortal heroes, everything would quickly and immediately erupt into total chaos. The "superheroes" of Faerun were something that many people found problematic with 3rd edition, and it seems that they're back in force. And because every Cormyrean guard is a total bumbler, the Harpers are also back.
Elminster's transformation at the end of the book essentially turns him into the biggest (and quite literal) deus ex machina I've ever seen. I'm really disappointed with this novel on many levels. The overall read was jumbled and not all that interesting, and filled with blatant, excessive clichés. Not recommended.