Are we there yet?
Tl;dr: The book is bad. The following review is just me rambling about the specifics of how and why it's bad, and wondering how come Butcher couldn't figure out storytelling by his forth book. I'll note that my now-established bias against this series definitely made the flaws much harder for me to ignore.
White council shenanigans again. A wizard is not allowed to kill with magic, no matter what. Not even in self defense. Harry escaped execution in the past only because it was both self defense and he was a minor. Imagine this in real life: You aren't allowed to kill, no matter what. Your life is in danger? not allowed to defend yourself. Your child is about to get murdered / raped / etc? sorry bro, just call the police afterwards. Or save your child and then get executed.
Naturally, this extreme "no killing" rule is here for two cliche (and overall bad) storytelling tropes: 1. killing is bad and children can't understand the nuance of when killing is justified and when it's not, so stories for children (and adult Americans, for some reason) often teach that killing is never justified, no matter what. Most stories circumvent the issues either by presenting a magical solution to every problem so no one has to die, or by making it a character conviction (the classic Batman "I have one rule").
Here, the "rule" is a council rule, combining it with the second excuse: 2. Children enjoy reading about irrationally oppressive authority figures, since being unable to understand the complexity of the adult world most children experience all authority as irrationally oppressive. Again, it's a common storytelling trope in books written for young children, and it feels completely ridiculous in the Dresden Files. Not that there aren't oppressive authorities in stories for adults (or in real life), but they usually aren't presented as irrational to the point of absurdity. I'm guessing this is also why Dresden practically has no non-lethal combat spells. For real. In a world where killing with magic is guarantied execution, a wizard detective with a tendency to end up fighting people never took the time to learn non-lethal combat spells. Because that would solve the problem, and then Butcher would have to come up with an actual story.
And the worst part? Dresden himself doesn't care. He lets a guy die in book 1, telling the reader he chose to let him die, while also implying he would have killed him directly had he been able to get away with it. So what's the point? Butcher uses storytelling tropes meant to teach us that killing is bad, but then writes his protagonist as one who wants to kill and just doesn't have the balls to do it because he's scared of the law. You can probably guess what I think -- that Butcher didn't spend much time thinking about this at all. He knew protagonists aren't supposed to kill, so he used the same old tropes hammered into him by every other story he'd read, but he also didn't like the tropes very much (because it makes no sense in the genre he chose), so he had his protagonist complain about it and find a passive way to commit murder. The result is a strange chimera of an adventure story for children and a mature detective noir. And to sum up, I think Butcher did a very bad job combining the two.
So, this series deals with killing in a very childish manner in general, but the way it's done also feels distinctively western/American (Christian?) to me. I've found that in most American supernatural/adventure stories, even those aimed at older teens (which is where Dresden is), there is often this "Batman rule" about not killing no matter what (or instead, a mechanism where killing leads to spiritual corruption). It always felt artificial to me, even as a teen, and it's one of the reasons I never liked American super-heroes, which often take this to the extreme. It's probably why I turned to Anime as a teen. (Sorry for using American/western writing as the main example. It was simply my personal introduction to this trope.)
Compare The Dresden Files with Cradle. Cradle's storytelling has its fair share of problems, but it treats the dilemma of killing as a story for older teens should: The protagonist simply tries his best not to kill people. He uses every chance he has to find a different solution. But if he can't, then he kills. It's not presented as a world-shattering or soul-corrupting event, and he isn't presented as a murderer. That's the mature version of the lesson: you shouldn't want to kill. You should try your best to find alternatives to killing. Lacking any other option (or the time to consider any other option), killing is an appropriate response to lethal danger. While Cradle is technically American, its origins and genre are not, and it shows. Compare with Harry Dresden's "This guy is trying to kill me, and I really want to kill him, but the cops will get me so I have to find a way to kill him without getting caught, which will also mean I'm not a murderer". I can't look up to him because he isn't inspiring, but also can't respect him because he's a manipulative coward. Either have him kill the guy or honestly try to find another way. Otherwise he's just a loser.
More Harry Potter stuff: I've discussed Butcher's "inspiration" in my review of Storm Front, but it doesn't end there. Barely into this current book, and someone tells Harry Dresden: "You have your mother's eyes", which anyone who grew up reading Harry Potter will immediately tell you that's their first association.
More on the plot of the book:
After spending the entirety of the previous book trying to bind Dresden to her, his godmother gives the contract to someone else. She says she had no choice, because she grew too powerful and had to give something away to maintain balance. If only she had thought about it earlier. Then again, had this book given up on the cheap drama there would have been nothing left.
Dresden is caught and rendered unconscious. Upon waking, his captors tell him they plan to kill him. Upon asking: "Why haven't you?", one of them answers: "good question". Brilliant.
After Dresden figured out parts of the antagonist's plan, he asks Morgan to bring help from the white council. But Morgan doesn't believe him (again), so Dresden has to fight alone (again). Who could have seen that coming.
Dresden enlists a group of werewolves called the "alphas". He tells them he's the one giving the orders, and none of them protest. It's a well know fact that an alpha likes taking orders, didn't you know? (I know it's just a name here, but it's still funny.)
Much of the plot's progression is just people (often antagonists) explaining parts of their plan to Dresden, and he in turn explains to them what he figured out. He even explains to the main antagonist how much of their plan he uncovered, and they in turn tell him which parts are correct and which parts are not. It feels as unnatural as it sounds. That's also the excuse for why they haven't killed him after capturing him: they wanted to discuss their evil plan with him first.
Then the antagonist leaves him alone to die, like some cartoon villain. Classic. Oh, and the evil plan is essentially destroying the world. Another classic. And no, the excuses the story gives for those don't make them any less cliche.
To top everything off, multiple characters keep telling Dresden how strong, brave, and smart he is. Because otherwise the reader wouldn't have known, I guess.