What makes Time, Ignorance, and Death inevitable?
Do they have something in common?
A pioneer of reducing that deadly "something" leads a short tour of where it's found and displaced.
Sayre's tour visits some unusual places. An immigrant neighborhood builds a microgrid. A remote radio telescope solves how to detect intelligence in the universe. A quantum mystery is resolved by our own incomplete view. All are related.
The tour's destination is a moral compass and hope in tragedy.