Deathwatch

"Gathered from the many Chapters of the Space Marines, the Deathwatch are elite, charged with defending the Imperium of Man from aliens. Six Space Marines, strangers from different worlds, make up Talon Squad. On a distant world, a new terror has emerged, a murderous shadow that stalks the dark, and only the Deathwatch can stop it. Under the direction of a mysterious Inquisitor Lord, they must cleanse this planet or die in the attempt."--Amazon.com.