thick of things

Noun

 * 1)  A central or major role in a situation; a position in which one is surrounded by or very involved in complex, changing events.
 * 2) * 1888, Joseph Augustus Seiss, Lectures on the Gospels, vol. 2, Lutheran Bookstore (Philadelphia), p. 767:
 * Christ calls for large ideas, bold enterprise, heavy undertakings, brave adventure, and heroic plunging into the thick of things.

Usage notes

 * Often used in prepositional phrases beginning with or.