Sandy Edwards (played by Toni Collette) is a director in a company that designs geological software in Perth, Western Australia. Her business partner manipulates her into agreeing to act as a guide for a Japanese businessman visiting mines in the Pilbara desert, in hopes that he will purchase the software. When Hiromitsu Tachibana (Gotaro Tsunashima) arrives, he treats Sandy like a chauffeur, and he seems more intent on self-discovery in the wilderness than on buying computer software. At first, Sandy is angered by his reserved, demanding demeanor. On their first journey into the desert, Hiromitsu, feeling insecure, talks more on his phone with friends in Japan than he does to Sandy. He also insists that she drive farther than planned. The terrain proves too much for the pair's vehicle, which becomes bogged down in the sand. After a series of desperate attempts to release the vehicle, including digging a dead man anchor, their winch burns out. Sandy wants to use Hiromitsu's phone to call people who can rescue them, but Hiromitsu refuses. This forces them to spend the night stranded together. The next day, Hiromitsu, conscious that his refusal had placed them in danger, wakes up much earlier than Sandy and builds a track of sticks over which they can drive out of the sand. The manoeuvre is successful. Now that they are on the road again, the ice breaks and a friendship starts between them that, in isolated surroundings uninterrupted by their work, grows quickly and honestly. Later, at a motel, they have sex. Only after does Sandy learn that Hiromitsu has a wife and children in Japan.
On another journey to scenic spots, Hiromitsu and Sandy share a quiet moment and kiss each other, eventually having sex again. Afterwards, Sandy runs into a swimming hole nearby. Hiromitsu follows her, diving into the shallow water before she can warn him, and disappears. Sandy frantically calls for him and, after a moment, his lifeless body resurfaces. In shock at his sudden death, Sandy struggles to deal with the situation, dragging his body into their vehicle and carefully washing it before driving for hours to the nearest town. Back in Perth, Sandy cannot comprehend the violent end to her journey. Reality intrudes in the form of Hiromitsu's grieving widow, Yukiko, and Sandy tries to understand how Hiromitsu's life had ended before she had understood his place in hers.