A sequel to Reynolds' previous book, Dark Apostle, this book continues to follow the career of Marduk, former disciple of the Dark Apostle Jarulek. Marduk continues his quest for power, with this book centering around unlocking the secrets of a Xenos artifact recovered in the previous book.
In my opinion, the previous book was middling, and really suffered when its only sympathetic character becomes a thrall to Chaos. This book turned out to be somewhat better, but still suffered from a lack of a really identifiable sympathetic character.
Marduk (a member of the Word Bearers traitor Space Marine legion, and a disciple of the dark powers of Chaos) has arrived at the world of Perdus Skyalla, to recover an Adeptus Mechanicum acolyte, with the assistance of a traitor acolyte Darioq. The world is currently under threat by a Tyrranid hive fleet, and the Imperial forces are busy trying to evacuate as many as they can before they declare Exterminatus (that is, killing every life-form on the planet with WMDs). Into the mix of chaos and confusion the Dark Eldar have arrived with the intent of capturing their quota of slaves from a populace that probably won't resist them.
On the note of a sympathetic character, we are introduced to Solon, a miner that adopts Dios, a boy who was the sole survivor of a Dark Eldar raid. We are lead through their struggles across an arctic wasteland as they try to reach the spaceport before the Tyrranids invade. While at the end they are successful, and the boy Dios survives (Solon sacrifices himself, so to speak, to ensure Dios survives), we learn with the very last scene that Dios is himself infected with the Genestealer taint, and that his survival essentially means that the infection will spread throughout the refugees, creating a beacon for the Hive Fleets to follow.
While the theme of the Warhammer 40,000 setting has always been hopelessness infront of insurmountable struggles and terror, there does come a point when this begins to fall flat. In some ways it is the opposite of the "Hollywood" character syndrome: in a Hollywood movie, you always know the main character will probably survive (and when he/she doesn't, its a big surprise), Warhammer 40,000 is the opposite. While reading about the stuggles of Solon/Dios, I could almost predict they would have a bad ending. And it did. Particularly when the primary character is a Chaos Space Marine, the book needs a sympathetic character that survives and has something of a happy ending. It is already difficult to identify with Marduk, so why couldn't we identify with the boy? The genestealer taint cheapens the sacrifices of Solon, with the only victory being that he can die with a clear conscious. While I understand this is the theme of the setting, constantly beating upon it makes the writing hollow and to an extent pointless.
That being said, it was a better book than the previous volume, and was more entertaining. It also sets up the next book (should there be one), with some crazy Necron action!