I read this book about 10-Aug-2003. I've read this book before. The book is copyright 1954. This note was last modified Monday, 19-May-2014 16:36:27 PDT.
This is book 6 of the "Lensman" series.
This note contains spoilers for the book.
The crashing finale of the lensman series, where two species are exterminated and one planet is really spectacularly destroyed (hit by two super-luminal planets coming in from another space). And a third species suicides. Doc Smith is not for the faint of heart.
We jump forward 20 or so years from Second Stage Lensmen; Kit Kinnison, son of Kimball and Clarissa, has just graduated from the Academy. He's immediately given his Release (made a Gray Lensman), and gets right to work. He also has four sisters, who have spent most of their lives hanging out with second stage lensmen, and hob-nobbing with the Arisians. These are not your normal teenagers.
In fact, they're scarcely human. They're the reason that Kimball and Clarissa's marriage was "necessary" according to Mentor. They're the product of the breeding program that the Arisians have been running for millions of years.
They do, in the end, destroy Ploor, and defeat the Eddorians once and for all, finally.
The immaturity of the children, combined with their tremendous knowledge and really tremendous potential (far in excess of the Arisians), is really rather well handled. Having superhuman characters on stage is nearly always disastrous, and Smith does pretty well with it.
Interestingly, particularly given when it was published, in a very prudish era, there are clear indications that the five children, Kit and his four sisters, are going to form a family together. After all there's nobody else good enough for them. The hints are quite explicit.