This is the forth adventure for Hank and Heather Heilsing and their team. They have faced vampires, swamp creatures, aliens and of course the occasional madman or two along the way but this time is different. The team is facing a power that has been waiting for thousands of years to get another chance to dominate mankind. Add to that the fact that through its influence a number of governmental agencies are poking into anything and everything that the team is doing. This could be the biggest test yet.