In "The Holy Grail," Zach Dorsey, now 23 years old and happily married to Sam, lives a peaceful life as a professor at Tulane University. But tranquility shatters when Pope Aloysius is assassinated, and Brother Guiden, Zach's trusted mentor, vanishes into the shadows for safety.
 
Once again, dire circumstances thrust Zach and Sam into a world-jetting adventure. This time, they must unravel the enigma of the "Holy Grail," a new Eve destined to save womankind. Guided by the Divine Feminine, their quest takes them to iconic locations in Turkey and Ireland, where they forge alliances to decode puzzles and grasp their mission's significance.
 
Meanwhile, the Antichrist and his formidable henchman, the Holy Seer, are relentless in their pursuit of world domination. They've abducted Royal Blood children to harness their powers and infiltrated key governments.