Hammer and Crucible is the first book in the Imperial Hammer series, a space opera novel, written by Cameron Cooper. A plot that starts being a more political/military one that evolves into one with astral consequences and a female main character are some of the elements we find in this novel.

Danny, the Imperial Hammer, decided to let her life pass and die, a rarity among the inhabitants of the Imperium. And that's until she was given the clue that the death of her son 40 years ago might represent a conspiration organized by the own Emperor; in the company of her granddaughter, she will start a run across the Imperium trying to discover the truth behind it.

With this premise, Cooper creates a compelling space opera, but whose pacing is extremely slow in my opinion. There are so many filler moments that while it helps build the characters, but don't give any meaning to the plot; we spend half of the book or so just traveling from place to place for the rejuvenation of Danny and for a little investigation.
In comparison, the last quarter is frenetic, and where the plot really takes significance.

Characters are the best elements of this book, especially because Danny is a really well-built one, a person whose hope was lost until she was given another reason to live; her grandchild complements well her during most of the story.
The concept of the array gaining conscience is quite interesting, but again, I think it was not developed enough in this book, in general; we only get a small taste before the novel ends.

Hammer and Crucible is a good introductory novel to the universe of the Imperial Hammer series, and if you like space operas, you will probably end up liking it. For me, it was probably not my cup of tea, but still a competent one.

Disclaimer: This review and score represent only my personal opinion. Team scores might vary.