This is a rather typical space opera by Doc Smith. It was written around 1960 so is a little more modern. The heroes are about prefect, the villains evil, all are fairly shallow.
Some ships occasionally disappear in hyperspace, so this is one of them. The story is how the crew copes, and deals with onboard pirates. Naturally, everyone carries their guns.
The story is about their survival when subspace problems happen.
Generally, the story is very short, there aren’t enough subplots, and little tension. Within the scope of Smith’s earlier works and others in similar genre’s it’s ok, but I think others are better.
This book is set in a fantasy world where magic comes through illuminations. The idea is interesting, the text involving the illuminations is well told and interesting. The rest of the book is a bit bland.