Karana and her brother Ramo spot a ship approaching the island. The Ghalas-at chief, Chowig, goes to meet the Aleut hunters and their Russian leader Captain Orlov, who want to hunt otter on the island.

The Aleuts set up camp and begin hunting. The tribe watches uneasily as the hunters take otter after otter from the kelp beds. The agreed-upon portion seems increasingly unlikely to appear.

When the Aleuts try to leave without paying, the Ghalas-at men confront them. The confrontation becomes a battle. Most of the tribe's men are killed, including Chief Chowig. Only a handful of warriors survive.

The new chief Kimki decides the tribe cannot survive on the island without their men. He sails east in a small canoe to seek help from the mainland, promising to send a ship for the tribe. Months pass. No ship comes.

A ship finally arrives — not Kimki's ship but a different one, sent by the missionaries. The tribe evacuates. But Ramo has been left behind, and Karana jumps overboard to return to him. The ship cannot come back in the storm.

Ramo sneaks away early one morning to retrieve a canoe from the other end of the island. The wild dogs — a pack of feral dog-wolves — attack and kill him. Karana finds her brother's body.

Karana decides to leave the island in a canoe, paddling toward the distant mainland. Her canoe leaks badly and she is forced to return. She returns to the island, accepting her situation — but determines to build a life rather than merely wait.

Karana moves out of the ruins of the village and builds a new shelter on a headland near the sea. She describes the process in detail — digging post holes, weaving walls, constructing a fence against the wild dogs.

Karana begins her campaign against the wild dog pack. She wounds the pack leader — a large dog with yellow eyes — with a spear, but cannot kill him. She finds him injured and, against all her intentions, nurses him back to health.

Rontu recovers. He follows Karana. He becomes her companion — sleeping outside her fence, traveling with her, fishing alongside her. Their bond deepens over seasons.

Karana hunts a sea elephant — a massive, dangerous bull — for its meat and oil. The hunt is grueling and nearly fatal. She succeeds, but is disturbed by the experience and resolves to stop killing large animals.

Exploring a part of the island she has avoided, Karana discovers a black cave with ancient figures carved on the walls. She also finds the skeleton of someone who lived there long before — and weapons that she takes.

A ship with Aleut hunters arrives again. Karana hides, watching from a distance. She hates them for what they did — but also watches with a hunger to see other people. She observes a young Aleut woman who comes ashore alone.

After days of watching, Karana approaches Tutok. They cannot speak each other's language, but communicate through gesture and expression. Tutok gives Karana a necklace. Karana gives Tutok her most cherished possession — a skirt of cormorant feathers. They exchange names.

The Aleuts finish their hunt and prepare to leave. Tutok looks for Karana before departing but cannot find her. The ship sails. Karana watches it go. She is alone again.

Karana rescues a wounded otter from a tide pool and nurses her back to health. She names the otter Won-a-nee. The otter becomes another companion — one she will refuse to shoot later even when hungry.

An earthquake shakes the island, destroying part of Karana's shelter and altering the coastline. She rebuilds. The event reinforces how entirely subject to the island's forces she is — and how fully she has made it home.

Karana tames two birds — a male and female that she names Mon-a-nee and Tainor. She also repairs the old village canoe and considers another escape attempt — but does not make it.

Rontu grows old and dies. Karana grieves quietly and buries him. She later finds a pup among the wild dogs that has Rontu's coloring — his yellow eyes. She tames him and names him Rontu-Aru: son of Rontu.

A white ship appears at the island. Karana watches from hiding, as she has trained herself to do. This time she recognizes it as different from the Aleut hunters' ship — possibly the rescue she has waited for. But she hesitates, and the ship leaves without seeing her.

A tsunami follows an earthquake. Karana retreats to high ground and survives, but her shelter near the sea is destroyed. She rebuilds on higher ground. The event reshapes the island's coast again.

Karana makes a longer canoe journey than before, exploring the area around the island. She finds caves, new fishing spots, and — briefly — sight of what might be the mainland to the east.

Karana spends the summer making a skirt of cormorant feathers — replacing the one she gave Tutok. The work is detailed and meticulous. She thinks about Tutok while making it. The skirt becomes a meditation on beauty and longing.

Aleut hunters return to the island again. This time Karana hides more efficiently and remains hidden throughout their stay. When they leave, she emerges to find her food stores undisturbed. She lets herself feel relief rather than hatred.

A chapter of accumulated time — Karana describes the cycles of the island's years: what comes in spring, how summer abundance is preserved, the fierce Pacific storms of winter, and how she has calibrated her life to the island's rhythms.

An unusually brutal winter. Food stores run low. Karana cannot fish in the storms. She becomes ill. She recovers. The winter's harshness tests everything she has built, and she holds.

Another ship appears — different again, clearly not hunters. Karana watches, then makes a decision: she lights a fire on the headland. The ship sends a boat. She is found.

Karana arrives at the Santa Barbara mission. The missionaries speak Spanish. They teach her to speak some Spanish. But no one who speaks her language is alive. She cannot tell anyone her full story. She is given a new name.

Karana's brief epilogue: she dies seven weeks after arriving at the mission. The novel's afterword acknowledges that the real Lone Woman of San Nicolas died this way — and that her language died with her. Nothing she said was recorded. We know her only by what she left behind.