This book is the first in the continuation series, Acorna's Children, following on from the original Acorna books, making it the eighth book overall featuring Acorna and the other Linyaari. The original books are a must-read if you are to understand the setting for these books, as very little background information is given in this novel, and events and characters from the previous stories are referred to frequently.
The story of First Warning centres around Khoriilya, Khorii for short, the daughter of Acorna Harakamian-Li and Aari from the original series, and her cat Khiindi. When a plague starts spreading through Federation space, Khorii and Khiindi are left for safety on Maganos Moonbase, but quickly they discover that they are the only ones who can really help. They encounter a diverse range of characters and make many good and useful friends as they battle the deadly new enemy.
I enjoyed the original Acorna series although I found it quite childish because the characterisation is very simple. This book is no better in this respect and the descriptions of the characters are often repeated. Despite this, however, I really got into the plot and devoured the whole of the Acorna's Children series within a few weeks. I would probably not re-read it, but it was fun. I would recommend this book and the whole of the Acorna series for teenagers most although it can still be enjoyed by adults.
The book is not complete in itself, the ending remains open for the sequel, Second Wave. It is currently available in both hardback and paperback.