Two children are stranded in the Australian outback and are forced to cope on their own.

In Sydney, Australia, a family lives in a high-rise apartment building, where the mother is preparing the meal and listening to a radio as she works. After school, the children, a self-possessed fourteen-year-old girl and her six-year-old brother, swim in the building's pool that has a view of the ocean, as the father, who is deep in troubled thought, watches them from their balcony. One day the father drives the children, who are still wearing their school uniforms, deep into the Outback. As the daughter sets out a picnic lunch on a large scarf and the little boy plays with his water gun and toy soldiers, the father reads in his car. Suddenly, announcing it is time to go, he pulls out a gun and fires several shots at them. The boy believes it is a game, but the girl understands the danger and shields her brother from seeing their father set the car on fire and shoot himself dead. Quickly, the girl retrieves the radio, the scarf and what food she can carry away and sets off with her brother, hoping to find her way back to civilization. Calmed by the irrelevant sounds of radio broadcasts, the girl leads the boy in the hot sun past wild creatures, many of whom are dangerous if provoked. When the sun finally sets, the boy is delighted to camp out overnight. In the daytime, hoping to see where they are, the girl leads him up a rocky hill and they walk along the ridge, where they get a view of the sea. When they finish drinking a bottle of lemonade, the girl makes a hole in a can of vegetables, from which they drink the juice. Recalling an uncle's story about his military training, the girl suggests that they eat salt and tells the boy they will stay in the desert a few days. She remains stoic, keeping the boy entertained, and when he tires, she carries him. They are dirty, exhausted and depressed when the boy spots a tree filled with fruit and parakeets surrounded by a muddy pool. Eating the fruit, the boy proclaims that it tastes "lovely." After washing, the girl scolds her brother to take care of his clothes so they will last. When he asks if they are lost, she replies simply that they are not. As they sleep, a boa constructor crawls over them and animals tread past them and in the morning they awaken to find that the water has dried up and the fruit has been eaten. Hoping that the water hole might refill again, the girl decides they will remain there. As they nap in the hot sun, the boy spots an adolescent aborigine who is pursuing an animal to kill it for food. He talks to them, but they do not understand his language. The girl calls to him, asking him to help them find water, believing that he should be able to understand her request. Her repetition of the word "water" is incomprehensible to him, but when the boy mimics drinking, the aborigine understands and shows them how to poke a hollow tube into the earth and drink through it. Assuming that he will take them to civilization, the girl and her brother accompany the aborigine, unaware that he is on a "walkabout," a solitary journey that a male of his tribe undertakes to mark his entrance into adulthood. He kills, prepares and cooks wild beasts for them, so they no longer go hungry, and leads them to a greener land, where there is plenty to drink. When the boy becomes ill from sunburn, the aborigine knows what to do. While they are resting, the girl suggests to her brother that the aborigine would like to play with his toy soldier, because he has never had one, but the older male tosses it aside. As they are still children, they frolic in trees and swim in ponds, but the girl and the aborigine, who are on the brink of sexual maturity, are watchful of each other. The girl, especially, remains vaguely uncomfortable and small events cause her to remember the horrible sights of her father's death. When the aborigine talks to the girl, she does not understand, but the boy soon learns to communicate with him. As they walk, the boy tells the aborigine a story, to which he listens, but, as the girl points out, he cannot understand. When the aborigine stops to draw a story in pictures onto a rock cliff, the girl draws a house, hoping to communicate that that is where she wants to go and the boy chatters his belief that the aborigine can take them to Mars. They pass very close to the homestead of a husband and wife who hire indigenous people to make small statues of animals that will be sold as souvenirs to tourists. Speaking in his language, the woman tries to hire the proud aborigine while he is scouting ahead of the boy and girl, but he rebuffs the woman, and the siblings remain unaware of how close they are to other whites. Although they seem far away from other humans, there are a group of scientists nearby, who lose a weather balloon, which the aborigine retrieves and brings to the girl and boy. When the girl instructs her brother to ask the aborigine how much longer it will take to get to their destination, the aborigine smiles and, using hand signs, answers that they will reach it that day. Soon they approach a homestead, but to the girl's sorrow, it is deserted. The aborigine talks happily to the girl, who does not understand, and he watches her when, inside the house, she cries after finding old photographs. When she asks him to get "water," still unable to say any word in his language, he understands. Unhappily, he shows the boy a road nearby, and then pursues a wild animal with his spear, while having visions of the white homesteader shooting the animals. When he returns to the house, he ignores the girl's hello. Later, he approaches her more forcefully than usual, his body painted to resemble a skeleton and the girl, now fearing him, shuts herself inside the house with her brother, who is too young to understand the nuances of the older children. As if carrying out a ritual, he dances throughout the night, although he is silently crying. When the boy tells her that the aborigine showed him a road, the girl decides that she and her brother should continue their journey without their companion. When she awakens in the morning, the aborigine appears to be gone. Looking forward to returning to her old life, the girl insists that they dress in their full uniform. She tells the boy that the aborigine left to be with his own people, but the boy knows better. He says that when he offered his pen knife as a gift to him, the aborigine did not take it and then leads her to where the aborigine is hanging, dead, in a tree. Disturbed, she asks her brother if he ate his breakfast properly sitting down, but brushes away the flies on the aborigine's chest. They follow the road to a set of buildings that were previously used for a now abandoned mine. The caretaker locks them out of the property, but tells them where they can wait for others to arrive. While they wait, they play around the old mineshafts. Years later, a businessman returns home and, pleased with himself, tells his wife that he has been promoted to the position vacated by an older man, who was laid off. As he talks about an impending salary increase that will finance a vacation on the Gold Coast, her mind wanders and she silently recalls idealized moments of the time she spent in the Outback with her brother and the aborigine.