Published in 2014, The Rule of Three is a young adult postapocalyptic novel by acclaimed Canadian author Eric Walters and the first book in the series of the same name. Known for tackling “what if” scenarios, Walters set The Rule of Three in his own neighborhood of Mississauga, Ontario, to explore the potential consequences of modern society’s dependence on technology. The story begins when a catastrophic global event instantly disables all computer-based technology, plunging society into chaos. Sixteen-year-old Adam Daley, whose vintage, computer-free car is one of the few that still runs, must help his family and suburban community survive the collapse of social order. The novel taps into real-world anxieties about the vulnerability of critical infrastructure, examining themes of The Fragility of Civilization and Social Order, Redefining Community and Leadership in a Crisis, and The Conflict Between Morality and Survival. The series continues with Fight for Power (2014) and Will to Survive (2017).

This guide refers to the 2015 Square Fish edition.

Content Warning: The source text and this guide contain depictions of graphic violence, death, animal death, and child death.

Plot Summary

Sixteen-year-old Adam Daley is in his high school’s computer lab with his best friend, Todd, when a sudden power outage strikes. Strangely, the failure shuts down all electronic devices, including battery-powered laptops and cell phones. After a brief assembly where the principal announces an early dismissal due to a presumed countywide outage, Adam discovers the true scope of the problem. In the school parking lot, only his old, computer-free 1970s Omega and one other vintage vehicle will start. Adam theorizes that a computer-killing virus or pulse has disabled all modern technology.

Adam gives Todd and his crush, Lori, a ride home. Along the way, the roads have become jammed with stalled cars, creating widespread chaos. Adam picks up his fourth-grade twin siblings, Rachel and Danny, and then drops Lori at her family’s farm, where he notes her father’s old tractor is still functional. He learns from another driver that the outage extends for at least 30 miles. Arriving at his suburban neighborhood, Adam is met by his neighbor, Herb Campbell, a knowledgeable but unsettling retired government employee. Herb reveals, via his old tube-powered shortwave radio, that the outage has also hit Detroit, making Adam worry about his father, a pilot who was grounded in Chicago.

Herb asks Adam for a ride to a pool supply store to buy a large quantity of chlorine. He explains the survival “rule of three,” telling Adam that the chlorine is for purifying drinking water once the municipal system fails. Leaving the store, they are confronted by a group of desperate men who try to take the car. Herb de-escalates the situation by revealing a holstered pistol and negotiating calmly with the men. That night, Adam finds Herb guarding the entrance to their street; looting and muggings are happening outside their neighborhood as panic and desperation set in. The next morning, Adam’s mother, Kate Daley, a police captain, returns home with a rookie officer, Brett. Over breakfast, Herb suggests that Kate organize civilian patrols of the neighborhood, but Kate doubts the necessity. Adam drives his mother back to her precinct, but on the way, they see a mob looting the local supermarket. Brett and Kate manage to gain control of the mob, and Herb organizes an orderly distribution of perishable food, averting further chaos. Realizing the rapid breakdown of society, Kate agrees to Herb’s proposal for an organized neighborhood defense. That evening, a patrol is formed using local police officers and civilian volunteers, who use a collection of old minibikes and go-carts.

A few days later, Adam, Herb, Todd, Rachel, and Brett drive to the Peterson farm. On the way, Herb is interested to learn about the ultralight airplane that Adam was building with his father. The craft is almost finished, and Adam is just a few flights short of earning his pilot’s license. At the farm, Lori’s father, Stan, approaches them with a shotgun, and they learn that he has had to fire warning shots at people trying to steal his chickens. Herb assesses the farm’s vulnerabilities and arranges for Adam and Todd to stay overnight to help build a perimeter fence, giving Adam his pistol for protection.

The next morning, Adam and Todd return home to reports of escalating violence. A neighborhood checkpoint is attacked, and a guard, Mike Smith, is killed. Amid these worsening conditions, Adam discovers Herb’s secret contingency plan: to evacuate a select group of 158 people with essential skills to the Peterson farm, abandoning the other 1,400 residents. Adam confronts Herb and proposes bringing the Petersons and their resources into the neighborhood to help everyone. Herb agrees to consider the plan. A few days later, they drive to the farm, and Herb convinces Stan Peterson that his family and farm equipment are needed to save the entire community.

The neighborhood organizes a convoy operation to evacuate the Peterson family, their livestock, and all their farm equipment. On the way, however, it is stopped at a roadblock, where Herb and Adam are taken hostage. Using a clever ruse and the threat of a concealed weapon, Herb disarms their captors and forces them to clear the road. Back in the neighborhood, a community meeting is held, and Adam gives an impassioned speech that unites the residents. A plan to fortify the community, now called Eden Mills, and become self-sufficient is put into motion. Construction begins on a perimeter fence, and Stan Peterson begins leading an effort to turn the neighborhood’s green spaces into farmland.

Adam finishes assembling the two-seater ultralight airplane he was building with his father and takes an impulsive, yet successful solo flight. The ultralight quickly becomes an invaluable resource for Adam’s community, and he begins flying regular reconnaissance missions to scout the land and gather information. Outside Eden Mills’s new walls, there are signs of violence and lawlessness. Most worryingly, Adam and Herb discover a group of heavily armed men living in a military-style compound in a nearby town. The men shoot at the ultralight, and Adam and Herb realize they have found a powerful new enemy. However, other groups are also coming together for survival, and Eden Mills forms an alliance with the neighboring community of Olde Burnham.

One day, the residents of Eden Mills hear explosions from Olde Burnham. Adam and Herb fly over at dawn and find the community has been destroyed by the military group, with hundreds dead. As they leave, a small enemy plane attacks their ultralight, but Adam’s maneuvering allows Herb to shoot the plane a down. Back home, they learn from a captured enemy soldier that their neighborhood is the next target.

Herb devises a plan for a preemptive strike on the enemy compound to provoke a counterattack and lure them into a trap at a bridge rigged with explosives. Adam and Herb provide air support, dropping grenades and Molotov cocktails on the enemy base and their pursuing convoy. As the full enemy force of several hundred men in over two dozen vehicles crosses the bridge, the explosives are detonated. The structure collapses, sending the entire enemy force into the valley below and eliminating the threat. Flying over the wreckage, Adam and Herb know their neighborhood is safe—for now.