Vox Tenebris: Warhammer 40,000 (Unabridged‪)‬

When the Fenris system is overrun by the forces of Chaos, the Imperium rallies to its defence, and Space Marines from many Chapters arrive to lend their aid to the beleaguered defenders. The battle to reclaim the worlds of the Space Wolves is waged on many levels - in space, on land and in the very seas themselves.

A Space Wolf and a Dark Angel must join forces when the rest of their strikeforce is slaughtered by daemons, deep underground. Unless they can find their way through the underworld back to the surface, they are doomed - but the trials that face them will test them to their very limit.