Sarah Vowell brings us the story of a national dispute involving Carlsbad Caverns in New Mexico, a sandwich, park rangers, scientists, and the United States Congress.

Genevieve Jurgensen and her husband Laurent lost their two daughters—Elise and Mathilde—at the ages of 4 and 7. Actress Felicity Jones reads from her book The Disappearance: A Memoir of Loss, in which Jurgensen tries to explain their lives and their deaths to a friend, in a series of letters.