Bloodline: A Sigma Force Novel
The Eye of God (Sigma Force)
The Doomsday Key: A Sigma Force Novel
The Judas Strain (Sigma Force)
Black Order: A Sigma Force Novel
The Last Oracle (Sigma Force)
The Sixth Extinction (Sigma Force)
The Bone Labyrinth: A Sigma Force Novel (Sigma Force Novels)
Map of Bones (Sigma Force)