We often think of demons appearing only in extravagant and extraordinary manifestations or working only through "bad" people. But the truth is more frightening than that. Most demonic activity takes place undetected, under the radar, and can even be hidden in our own prayer lives and in the churches where we attend Mass. Subtlety, illusion, and deceit are the preferred tactics of Satan's army of fallen angels, and they are waging an invisible battle...