The novel begins with the narration of a girl named Karana. She is twelve years old, and she lives with her family in an island village named Ghalas-at. Her family of six consists of her six year old brother Ramo, Ulape her elder sister and her father Chowig, who is also Ghalas-at’s chief.
The story starts with Karana spotting a ship from the hills of their island. She and her brother Ramo go to collect roots for in the hills. They notice the ship as a “red winged gull” as described in the story. Ramo does not get that it is a ship because he had never seen one. Although Karana had never seen one as well, she had heard about them from her ancestors and was smart enough to figure it out.
The people of the whole island get alarmed when the ship reaches the shore of the island. The men of the island get armed and take position on the beach for their unannounced guests might bring trouble. Yet, the ship sends a small boat to the shore. The person who tries to negotiate with chief Chowig addresses himself as Captain Orlov. The party has come all the way from Russia, and they are called the Aleuts. They came to hunt otters, so that they could sell pelts to the mainlanders. For this reason they needed a place to stay and island of the blue dolphins was an ideal spot to camp.
Captain Orlov tries to negotiate with Chowig. But Chowig is shown as a fair and strong man who agrees to the terms only when Captain Orlov agrees to give half the otter pelts. This was reasonable for both parties. Although he lets the Aleuts camp on their island, he also creates awareness in his people because they did not have a friendly history with the Aleuts. As the chief quotes, “They are people who do not understand friendship.”
As the story progresses at a slower pace, we see how the tribe people and the Aleuts keep an eye on each other. The tribesmen were worried about their share and the Aleuts were interested in what the tribesmen were up to.
The story starts getting a little intense when Ulape spots a school of white bass. She runs to her people without wasting a moment, as the white bass were special and they might escape. The tribe people rushed to the place and caught fourteen white bass in total. They had a good feast. It was a happy moment until the Aleuts came looking for share of the white bass. Chief Chowig refused to give them the share they demanded because he had his own people to worry about. The Aleuts were not pleased by this.
Finally the hunt of the Aleuts was over and they were all prepared to return to their mainland. The only inconvenience was that captain Orlov did not pay the share he promised. When the tribe people went up to him asking for their share, he offered them three chests of beads and iron spearheads. This lead from a quarrel to a full blown war between the tribe and the Aleuts. The Aleuts won the battle because they had a canon. With their canon they wiped out more than half the men of the tribe. Chief Chowig was one among the fallen men. After that the Aleuts left.
After the Aleuts leaving, the island was never the same. There were a few people left. And they had to work more and more to maintain their lifestyle and more importantly, to survive. The men who did the hunting and harvesting had fallen in the war. The new chief Kimki decided that women would have to take place of the fallen men as there were not able men left to fill the gap.
Everyone started working hard and did their duties according to instructions. They also kept an eye for the ship for the Aleuts might return to kill everyone. They overcame their gaps, but what they did not overcome was the sadness they were left with. Chief Kimki decided that he would cross the ocean and go to the country that lies across it to find a new home for his people. Many suns had passed after Kimki had left, but there were no signs of his return.
The days that past were very numb for the people of Ghalas-at. One day, they spot a ship approaching their shores. Everyone felt intimidated. They started preparing to escape, which they had thought of in case the Aleuts might return. Fortunately enough for the people of Ghalas-at, the ship turned out to be people whom Kimki had sent to rescue his people.
Everyone was very happy and excited about leaving the island. This is where the story takes a turn when everyone realizes Ramo was left behind. This was because he went back to grab his fishing spear which he had left behind without anyone noticing. Karana begs the white men to go back for his brother, but Matasip tries to reassure her that the ship would return for Ramo within a few days. Karana quickly thinks and jumps in the water to return to her brother. She swims back to the island and reunites with her brother Ramo.
Karana and Ramo were doing everything necessary to survive on the island by themselves. However, Ramo wanted to do more and one early morning he leaves to collect a boat which they had hidden behind the rocks on the south part of the island. Karana waits the whole day for Ramo to return. When she goes to seek her brother, she finds out that Ramo never reached the location of the boats. He encountered some wild dogs and died fighting them.
This was a heart breaking event for Karana. She had lost everything. Now the only hope for her were Matasip's words. That the ship would return. She passed her days waiting for the white men to return with their ship. Many suns and moon pass, but there was no sign of the ship. Karana once tries to escape the island on her own on a small boat. She has to return to the island because after having rowed for a day and a night she realizes that her boat was leaking.
After returning to the island she realizes how much she loved the island and never wanted to leave again. Now she tries to do everything to survive on the island on her own. She makes a decent house and creates weapons to protect herself from the wild dogs. She even kills a few wild dogs which killed her brother Ramo. She tries to hunt down a sea cow, but fails when the sea cow engages a fight with another sea cow and dies on its own. In the process Karana gets herself caught in the fight and injures her leg severely. To recover, she had to rest for five days.
During this time, she also finds a cave full of paintings in the walls. She could infer from the pictures that this cave used to be home to her ancestors. So, Karana decides to make this cave her second home.
She also encountered the leader of the dogs in the cave. She injures the dog badly. For some reason she does not shoot the last arrow to kill him. Rather, she saves the dog, revive it to full health and becomes friends with it. She names him Rontu.
Rontu becomes an excellent company for Karana. She realizes how lonely she was before she found Rontu. However, she was still worried that the Aleuts might return and to be on the safe side, she creates a small boat from the old ones of the tribe. During testing her new made boat, Karana discovers a cave around the island. She decides to store food and supplies in the cave. After a while she discovers a devil-fish and decided to hunt it down.
To hunt the devil fish, she starts making big spears with a string attached to it. So that she can throw it to distance and reel it in. When she was not hunting the devil fish, she spent her time by making new dresses and jewelry for herself. One day when she least expects, she manages to spear the devil fish. However, she and Rontu both gets injured in the process.
One day the Aleuts return. Karana was not moved because she had been expecting them. She tries to hide from the Aleuts. She notices that the Aleuts brought a girl who does their chores while they are out hunting. One day the Aleut girl surprises her. She was afraid at first. But slowly she becomes friends with the Aleut girl named Tutok.
One day the Aleuts leave the island. After that Karana distracted herself by adopting and treating injured animals the Aleuts had left behind. She adopts an otter, which later gives birth to two baby otters and they discouraged Karana from hunting animals.
Rontu passes away on a summer day. She grieves greatly for Rontu. She arranges a funeral for Rontu and stops counting her days on the island. Eventually, she decides to have a new pet dog which looks like Rontu. She tranquilizes the whole pack and kidnaps the dog and makes it her pet. She names the new dog Rontu-aru, “the son of Rontu”.
Finally, after a few years, the white men return with their ship. This time they invite Karana to her camp and make her wear uncomfortable clothes. When they finish hunting on the island they take Karana with them. Karana takes her beautiful jewelry, Rontu-aruand two songbirds with her as well.