Book Recs

I am NOT a reader, but am wanting to get into a book. What is the one book/ book series? That you’d recommend that has a similar vibe to the lore of ER? I love a deep lore exploration that feels very grounded. I love the gray area in the ER lore of everything being done for reasons and they’re all explored so you understand the why. Not looking for a classic good vs evil book if that makes sense.