Francisco Cantú is the book’s author and its primary narrator.

He was raised in the Southwestern United States mostly by his mother. The book follows several years of Cantú’s young adult life after graduating college, starting when he joins the US Border Patrol as an agent at age 23, serving from 2008 to 2012 in Arizona, New Mexico, and Texas. He returns to civilian life after receiving a fellowship to study and research abroad. He later attends graduate school for writing while working as a barista, which is where he meets José, an undocumented migrant worker. He uses his experience with the Border Patrol and his ability to speak English and Spanish to assist José’s family after José is deported.

Cantú has a strong relationship with his mother, who appears throughout the book via in-person visits and phone calls.

She raised Cantú in the American Southwest. The daughter of a white mother and a Mexican immigrant, she had a successful yet complicated career as a park ranger for the US National Park Service. She passes her love and respect for Mexico, as well as her love of nature and the desert, on to Cantú, who feels drawn to the desert landscape as an adult.