The novel opens in a domed birthing lodge built in the traditional style of the Anishinaabe, an Indigenous people of the Great Lakes region. A young woman gives birth to a baby girl with the help of two midwives. The baby's grandmother conducts a naming ceremony, recounting a recurring dream of following a beam of light through birch trees until she found a small purple flower. She names the baby Waawaaskone, meaning "a flower" in Anishinaabemowin, the Anishinaabe language, and declares that the child "is a light that will help lead the way out of this darkness" (6).
Two days later, 15-year-old Nangohns, the baby's aunt, pulls in a fishing net and finds only 13 undersized fish, roughly half the expected catch. The settlement, Shki-dnakiiwin ("new village"), is home to about 50 people. Nangohns's father, Evan Whitesky, led the survivors here roughly 10 years earlier after a permanent power outage collapsed civilization, an era they call Jibwaa ("before"). The community sustains itself through hunting, fishing, and gardening, but manufactured tools like nets, knives, and ammunition are irreplaceable and wearing out.
At a community meeting, the eldest member, Walter, proposes sending a scouting party south to find a route to their ancestral homeland on the north shore of the Great Lakes, a place called Wiigwaaswaatigoong, "where the birch trees grow by the big water," from which their people were forcibly removed generations ago. Candace, a former band councilor, voices opposition: Her older son Isaiah and Kevin, Tyler's younger brother, left on a similar expedition four years earlier and never returned. Walter privately asks Evan to help lead the mission.
Nangohns insists on joining the expedition, arguing she is one of the community's best hunters and that staying put to slowly starve is equally dangerous. Her parents resist, but after debate, the plan is approved. Six walkers are announced: Evan; Nangohns; Tyler, Evan's closest friend; Cal, a young hunter and Isaiah's brother; Amber, Cal's partner and a midwife; and J.C., Walter's nephew and the group's eldest member.
After a farewell ceremony, the walkers head east through the abandoned old reserve, Gaawaandagoong, where nature has reclaimed the crumbling houses and rusted vehicles. Evan retrieves four handguns from a buried cache, weapons that once belonged to Justin Scott, a violent outsider who terrorized the community during the first winter of the blackout.
Over the following weeks, the group travels south along rivers and lakes, hunting small game and foraging. J.C. recounts an ancestral story about their people's forced relocation from the Great Lakes, during which a man was lost to the river's deadly current. A black bear raids their camp one night, stealing their rifle and some supplies.
They enter Gibson, a city that once held 100,000 people, under cover of darkness. The devastation is total: Every building has been gutted or burned, and the city is devoid of all animal life. At city hall, Nangohns discovers a map with red markings labeling areas to the south and east as "DEAD LAND" and "DEAD LAKE." Morale wavers, but Nangohns rallies the group, arguing that the young generation deserves a voice in the world they will inherit.
South of Gibson, on the 20th day, J.C. slips on wet rocks and suffers a severe leg fracture. Amber sets the bone, but J.C. will be unable to walk for at least a month. While the others scout for shelter, J.C. tells Evan the group must continue without him. When Evan steps away, J.C. dies by a self-inflicted gunshot wound. After four days of funeral rites, the walkers continue south, now five.
Days later, Nangohns spots a cellphone lodged in a tree fork, and Evan recognizes it as Isaiah's by its distinctive case. Following a trail of cloth markers, they reach a meadow where Nangohns hears children speaking Anishinaabemowin. Armed residents escort them to Saswin ("the nest"), a small settlement led by Linda, an elderly former university professor. Linda tells them Isaiah and Kevin arrived years ago, stayed the winter, and left heading south, leaving the trail markers.
Linda explains that Saswin was originally a land-based language and culture camp that became a permanent refuge after the blackout. Biiyen, a community member, describes how intense northern lights preceded the total collapse of power grids and communications, followed by violence, epidemics, and nuclear contamination from unmaintained power plants in southern Ontario. Linda proposes that the walkers' people settle near Saswin to build strength before connecting with other Anishinaabe communities believed to survive on islands in the Great Lakes.
After five days, the walkers resume their journey. In an abandoned highway town, they encounter a symbol painted on buildings: a sideways cross resembling a rifle. Gunfire erupts nearby, and they flee. After sheltering in a remote cottage, armed men in camouflage ambush them at dawn with racist threats. A burly red-haired man among the attackers suddenly turns on his companions, killing them. He identifies himself as Zhaabdiis, an Anishinaabe man from Baawaating (Sault Ste. Marie) whose mixed heritage allowed him to pass as white.
Zhaabdiis explains that he spent years moving between survivor communities before encountering the Disciples, a white supremacist militia that expanded across the Midwest after the collapse. He joined under a false identity to survive, waiting for a chance to escape near his homeland. He warns that other Disciple patrols operate in the area. While scouting ahead, the group spots a peaceful settlement with functioning turbines, but Zhaabdiis recognizes a Disciple recruit named Holden there, and they flee.
Two brothers, Anakwad and Giizhik, approach their campsite at dawn. They live on the big island the walkers seek and confirm it is inhabited. They provide directions: Follow the river south, then look east for birch trees leading to the shore.
At a major highway crossing, Disciples ambush the group, capturing Nangohns, Evan, Amber, and Zhaabdiis while Cal and Tyler escape into the bush. The sergeant recognizes Zhaabdiis by his alias. Zhaabdiis replies, "These are my people" (274), and the sergeant shoots him dead. Holden, among the Disciples, reveals he has already massacred the peaceful turbine settlement. As the Disciples debate the captives' fate, Anakwad and Giizhik attack from the trees with bows. In the firefight, Evan grabs a fallen pistol and fires, but a stray bullet strikes him in the abdomen. Amber, who had secretly loosened her bindings, frees the others. They carry Evan to the lakeshore and row out onto Lake Huron.
They reach the island by morning, arriving at a harbor town called Oodenaang. Noodin, a doctor, examines Evan but cannot save him. Ogimaa, a community leader, explains that roughly 500 people live across the island with room for the northerners. Evan drifts in and out of consciousness, describing a dream of bouncing between islands along a beautiful shoreline, with Anishinaabek cheering from every landing. He asks to be taken to the water. His companions carry him to a rocky overlook, where each says a farewell. Nangohns cradles her father's head in her lap as the community sings a traveling song. Evan hums faintly along before he stops breathing as the sun touches the horizon.
In the epilogue, set 11 years later, 12-year-old Waawaaskone picks blueberries with her grandmother Nicole on the island's shore, preparing for her coming-of-age ceremony. She speaks fluent Anishinaabemowin and knows her grandfather only from a faded photograph. Nicole reflects on the community's migration south, carried out in stages the summer after the walkers returned, with some members settling at Saswin. Waawaaskone asks whether they will always stay here. Nicole answers in Anishinaabemowin and then in English: "We'll always be here" (300).