Makina is a young switchboard operator in Little Town who fluently speaks Latin, Anglo, and Native. Her linguistic skills and discretion make her a trusted messenger for both the townspeople and the local criminal leaders known as top-dogs. Fiercely protective of her independence and her family, she agrees to cross the border into the North to locate her missing brother.

Makina's brother is a young man who left his family in Little Town to search for a piece of land his father allegedly owned across the border. He ignored his mother's warnings and sent only three brief messages home before ceasing communication entirely. His continued silence drives his sister to cross the border to find him.

Cora is Makina's mother and a formidable businesswoman in Little Town who commands respect from the locals and even the criminal top-dogs. She offers her children a profound sense of safety and comfort. Distrustful of men regarding important matters, she specifically entrusts her capable daughter to travel North to retrieve her son.

Chucho is a tall, wiry smuggler hired by the top-dogs to guide Makina safely across the border river into the North. Unlike typical coyotes who exploit migrants, he exhibits a protective loyalty toward Makina. He acts as her primary defender during the perilous crossing and subsequent encounters with border patrols.

Mr. Double-U is a pale, heavy-set man and one of Little Town's local crime bosses. Because Cora helped him out of a difficult predicament in his youth, he maintains a friendly and respectful attitude toward her daughter. He agrees to arrange Makina's safe return from the North without asking for anything in exchange.

Mr. Aitch is a cunning top-dog in Little Town who originally convinced Makina's brother to travel North by showing him a dubious land deed. He agrees to help Makina cross the border, but only on the condition that she acts as a courier and smuggles a mysterious package to his exiled rival.

Mr. Q is a local top-dog in Little Town who employs a highly precise but cryptic way of speaking. Makina previously worked for him as a messenger during emergency political negotiations. He promises to provide Makina with assistance once she successfully crosses into the North.

Mr. P is a blonde top-dog who fled Little Town and currently lives in exile in the North after a turf war with Mr. Aitch. Operating out of a baseball stadium, he surrounds himself with armed guards and waits for the package Makina smuggles across the border.

The Young Man is a traveler who attempts to grope Makina on a northbound bus, earning a swift and painful physical correction from her. After learning a hard lesson about respecting women, he travels to a Northern city and finds work in a restaurant kitchen.

Makina's little sister remains in Little Town while Makina travels North. Makina worries constantly about her younger sibling, wishing she could stay to teach her how to defend herself against the violence and misogyny present in their society.

The Rancher is an armed vigilante who patrols the border territory. Believing that Chucho is intruding on his own illicit human trafficking operations, he initiates a dangerous standoff with Chucho and Makina shortly after they cross the river.

The Old Man acts as a guide for Makina upon her arrival in the Northern city. He helps her evade undercover police and directs her to the baseball stadium, while also providing her with a slip of paper containing an address where she might find her missing brother.

The Old Woman lives in the North and immediately reminds Makina of her own mother. She previously fed and assisted Makina's brother when he arrived in the North sick and lost, eventually finding him a job with a local family.