In rural Australia, expatriate American truck driver Patrick Quid pulls into a motel for the night. There, a man in a green van checks in with a female
hitchhiker, whom Quid had passed by because of trucking company policy. In their motel room, the hitchhiker strums a guitar while the man unpacks a new guitar string and forms it into a noose. He winds the string around his gloved hands and uses it to
garrote the woman. Quid wakes the next morning in his truck. His pet
dingo sniffs at the garbage outside the motel, and Quid notices the van driver watching from the room's window as the garbage truck picks up the bags. Quid loads the refrigerated trailer with pork carcases, and sets off for
Perth on the
Eyre Highway. On the road he passes a nagging wife and her family and a cautious man hauling a sailboat. He repeatedly passes a female hitchhiker, Pamela Rushworth, who he does not pick up. The wife, Frita, creates a roadblock by streaming toilet paper across the highway. Quid stops and she climbs into his cab and orders Quid to catch up with her husband, who left her at the side of the road. They play
20 Questions to pass the time. Frita mentions a woman's murder and his nonchalant answers disturb her. She suspects he might be the
serial killer from the news. Quid stops the truck after seeing the green van parked along the road. Its driver has trash bags and an
esky; he appears to be burying the bags. When the van driver notices Quid watching him through binoculars, he abandons his work and drives away. Later, at a roadhouse, the van driver assaults Quid's dingo. Quid gives chase, but is hindered by the slow-driving boat owner, who refuses to let him pass. Eventually, Quid smashes the boat that swings to block as he passes, but the van is too far off to catch. Quid picks up the repeatedly encountered female hitchhiker, Pamela Rushworth, the daughter of an American diplomat. Quid urges Pamela to let her father know that she is alright. At a
service station, they notice the van parked near the restroom. Seeing that someone is in the toilet stall, Quid thinks he has the killer cornered and leaves Pamela to investigate the van. While reaching for the esky inside the van, Pamela realizes that the driver is sleeping on the floor. In the restroom, a biker emerges from the stall. Quid rushes outside to see that the van is gone. When Quid catches up to the van, he believes Pamela is chatting happily in the passenger seat. Later that night, Quid notices the van parked off the side of the road and pulls over to investigate. He hears people giggling in the bushes nearby and mistakenly assumes that Pamela and the van driver are having sex. He breaks into the van and finds that the esky only contains food. Quid arrives at the outskirts of Perth and, while reporting to the
weigh station, spots the van. He follows it through the streets of Perth, trailed by the police. Eventually the van reaches a dead end and Quid's truck becomes stuck in the narrow alleys. The van driver approaches Quid's truck and attempts to strangle him with a
garrotte, but Quid disarms him. When Quid starts to strangle the van driver with the garrotte, the police arrive and assume that Quid is the killer. Upon freeing a gagged and bound Pamela from the van, the police realise Quid is innocent, and catch Pamela's captor while he is trying to escape through the crowd. Pamela scolds Quid for abandoning her to appease the dangerous van driver who caught her searching his van. After delivering the meat shipment, Quid relates to Pamela that after he had found his trailer door open and discovered the load weight some kilos over, he had presumed that the van driver had killed her and disposed of her inside his trailer. At the meat facility, a woman cleaning out the trailer is brushed by a guitar string hanging from the ceiling. When she tugs at it, a human head falls into her soap bucket. ==Cast==