First off, as I started reading this book for the first few chapters, I was disappointed in the writing style and the choppiness of the words the authors used. There really was no background at the start as in most Star Trek books, you were just thrown into the middle of a mission. Toward the middle half of the book it got better, both story and writing, so the average overall comes to three stars.
Basically, the foreign foes are the Hidran and Klingons who have a long history of fighting. Well, Picard and associates are sent to settle a crisis on the planet Velex. The Klingons need something from the Hidran and vice versa. Well, this planet already has a Federation prescence of scientists there, studying the field of so called grain. This grain however, rejuvenates ones health if eaten. Well, during the Hidran/Klingon proceedings, which are full of conflict, Worf apparently kills one of the Hidran ambassadors in private, and this sets the stage for Picard being taken hostage by the Hidran. Meanwhile, Riker and Troi, get beamed below ground into a maze of machinery, some of which start attacking them...and they have to figure a way out of there.
Aboard the Enterprise, Data is in command and one of the scientists from Velex gives him the grain and he trys it out.
Afterwards, Data has this premonition that Geordi and all Klingons are bad and he must destroy the Klingons in orbit around Velex and then take off to their homeworld Qo' NoS to settle matters there.
So, basically the book is a mystery in why Data is acting the way he is, and how can he be stopped...with Picard and most of the crew stuck on Velex with irritable Klingons and Hidrans about to kill each other. Only Geordi, without his VISOR, which malfunctions after beaming back from Velex can try and stop Data. He actually fails, but other things take place on the planet that may settle this whole conflict, and Picard must figure it out.