The phrase "core mystery" refers to the central or main question or puzzle that needs to be solved in a situation or story. It represents the most important and intriguing part of the mystery that needs to be uncovered or understood. Full definition
This community has as its core a mystery to the human experience, and a sense that story and imagery can persuade at least as well as logical, more strictly factual arguments. (firstthings.com)
Whatever my apprehensions, I grasped that this was the essential transaction, the core mystery of communication. (firstthings.com)
15:29 - Fascinating insights into the core mystery of Huntington's disease from Nopoulos: what does the normal huntingtin protein do? (en.hdbuzz.net)