Adam is a 16-year-old high school student who possesses an old, computer-free 1970s Omega car and is building an ultralight airplane. These vintage technologies suddenly become invaluable assets when a global blackout disables modern electronics. He takes on significant responsibilities to help protect his family and organize his suburban neighborhood's defense.

Herb is Adam's elderly neighbor, a retired government employee with a secretive background involving intelligence work in unstable countries. He possesses a shortwave radio, concealed weapons, and a hardened survivalist mindset. Herb quickly acts to secure resources like chlorine and organizes the neighborhood's defense structure, anticipating the rapid breakdown of society.

Kate is Adam's mother and a captain at the local police precinct. She initially tries to adhere strictly to law enforcement protocols and jurisdictional rules but soon realizes she must adapt to the new reality. She leverages her formal authority to organize and legitimize the neighborhood's civilian patrols and defense committees.

Todd is Adam's best friend, a typical teenager who initially views the power outage as a minor inconvenience and an excuse to get out of schoolwork. He provides comic relief and maintains a carefree attitude, participating in community defense tasks without fully grasping the long-term severity of their situation.

Brett is an inexperienced rookie police officer thrust into extreme circumstances. He proves to be action-oriented, brave, and aggressive, displaying a capacity for violence that makes him an effective guard for the community. He thrives in the post-crisis world where social restraints are weakened.

Lori is Adam's high school classmate who lives on a farm on the outskirts of their suburb. Her family's property, complete with a working tractor, well water, and livestock, becomes a vital asset to the neighborhood. She provides emotional support to Adam and actively participates in the community's survival efforts.

Rachel is Adam's younger sister, a fourth-grade twin. She loves horses and is initially shielded from the full severity of the crisis by her older brother and mother.

Danny is Adam's younger brother, a fourth-grader. He relies heavily on his older brother and mother for protection and reassurance as the comforts of their normal life disappear.

Stan is Lori's father, an agrarian man who owns a farm near Adam's neighborhood. He possesses valuable agricultural knowledge, livestock, and equipment, which make his property an early target for scavengers and thieves.

Susie is Lori's mother. She demonstrates quick thinking and defensive capabilities, devising a peaceful system to provide desperate neighbors with water while protecting her family's farm from direct threats.

Sergeant Evans is an experienced police officer who struggles to process the sudden, violent collapse of law and order. He organizes the community's early defense checkpoints alongside civilian volunteers.

Howie is a police officer under Captain Daley's command. He guards the Peterson farm and mans the community's walls, experiencing firsthand the moral compromises required to keep the neighborhood secure against desperate outsiders.

Adam's father is a pilot whose absence deeply affects his family. He and Adam were building an ultralight airplane together before the crisis, an ongoing project that ultimately proves critical to the community's survival.

Mr. Gomez is a resident of Adam's neighborhood who steps up to help secure the streets. He works alongside the police officers to establish checkpoints and scavenge for resources.

Mr. Nicholas is an engineer who uses his expertise to design rainwater harvesting systems and plan the digging of wells. His mechanical skills help the community transition toward self-sufficiency.

Judge Roberts is a community leader whose formal status lends legitimacy to the neighborhood's new structure. He helps convene a civilian court to handle internal disputes and maintain a sense of civic order.