The techno-mages are going into hiding. The Shadows have basically given them an ultimatum. Join they or be destroyed. So the mages have decide to abandon their homes and gather at a secret hideout. The plan calls for an elaborate deception. They will gather on Babylon 5. They have to use misdirection to convince the Shadows they are on one vessel that will be destroyed by them. The reality is that they escape on another and convince the Shadows they have succeeded in destroying them.
As this is going on Galen is assigned to accompany one of the Circle to a Shadow stronghold on the rim of the galaxy. It is a mission of intelligence gathering but Galen does have the hope of meeting the renegade mage Elizar who is responsible for killing the woman he loved. A confrontation does occur with Galen finding out the secret of the techno-mages. That the tech they use originated from the Shadows.
The second book is an improvement over the first. We find out that the Shadows were the ones that gave the tech they use to the race that founded their order. Only the tech enhances aggression and need to compete which destroyed the race. The whole lie is they have been dependent on the Shadows for their tech. Now the Shadows are demanding payback and they know they have to flee. Galen discovers the truth and also the destructive power he has managed to uncover. The book skillfully integrates into the events of the TV series. So we get some behind the scenes of the events that happened. The book did at some places drag a bit but was for the most part an interesting read.