In a world overtaken by a virus that turns people rabid within 48 hours, the Rose family—Andy, Kay and their baby Rosie—are living safely on a houseboat in rural Australia. Short on food, Andy investigates an abandoned sailboat and retrieves various supplies. Later, Kay goes to collect more, but is attacked by a rabid human inside. Meanwhile, an Aboriginal girl, Thoomi, attempts to protect her infected father by feeding him wildlife and keeping him locked up while her mother is frantically searching for her. Andy discovers Kay in the houseboat, trying to stop the bleeding from a bite. They set out to find a hospital, but crash after avoiding a man in the middle of the road. Kay is impaled and Andy faints from shock; he wakes hours later and is bitten by a turned Kay as he gets Rosie out of the car. Andy prepares to defend himself against the man, noticing he is Infected. Thoomi appears and dissuades Andy from hurting her father. Andy finds a ute and attempts to hijack it, but is stopped by its trapped owner, Vic. Andy frees him and they escape to Vic's shelter where Andy meets Lorraine, who he assumes is Vic's wife. He leaves Rosie with Lorraine and leaves with Vic. Vic attracts the infected by imprisoning healthy humans inside cages as bait; Andy is perturbed to see Thoomi trapped. That night, Andy attempts suicide, but Lorraine stops him and confesses that she is not Vic's wife and knows he is infected. Vic knocks Andy out, and he awakens in the same cage as Thoomi. They agree to help each other escape by using the combined force of many infected to open their cage; they return to the shelter, rendezvousing with Lorraine and Rosie. Vic shoots at them as they escape, and Lorraine uses herself as a shield and is killed. The following morning, Thoomi runs off after Andy says her father will not get better. Thoomi looks for her father, finding him straddled atop a tree, dead. Andy arrives to comfort her, but leaves when he cannot console her, as she blames him for delaying her. Thoomi remains at the tree grieving, but is able to hear Rosie's cry and catches up with Andy. They travel by motorboat to the campsite where Andy previously saw a family, inspecting the caravan in which they were staying. Andy leaves with Rosie to go find the family, while Thoomi stays in the caravan. He meets the father, who has been bitten. The father offers Andy a revolver once he uses four of the bullets to kill himself and his family. The father executes his plan, and Andy collects the gun as intended and debates whether to shoot himself as well. Thoomi rushes to them, and they travel towards nearby smoke. As they pass through a train tunnel, they encounter Vic. Thoomi hides with Rosie inside a parked vehicle on the tracks, while Andy tries to distract Vic. The two men fight. During the struggle, Vic manages to obtain the revolver and shoot Andy. He rises to check on Thoomi and Rosie, who Vic is cradling, lamenting the death of Lorraine. He tearfully hands over Rosie so that Andy can renew his walk. Andy has another lapse, almost indulging in decayed meat. With little time left, Andy asks Thoomi to promise to look after Rosie, and then prepares himself for the transformation by placing a guard in his mouth, binding his wrists, and wrapping meat on a stick. They catch up to the Aboriginal warriors as they finish killing several infected, but Thoomi calls out to them with a whistle, drawing the attention of her mother. Thoomi and Rosie are riding Andy, who is detained by the warriors while Thoomi and Rosie are welcomed back. She takes out Kay's perfume bottle and sprays it, the smell pacifying Andy who seems to acknowledge Rosie is finally safe. Thoomi allows a warrior to put Andy out of his misery. The Aboriginal people are seen travelling to a refuge of their people where they are welcomed heartily. As Thoomi and her mother inspect Rosie, the words Thank You are read on her stomach, apparently written by Andy in the white paint which Thoomi and the warriors have used to disguise their scent from the zombies.
Cargo received positive reviews from critics, praising its emotional depth and Freeman's performance. On review aggregator website Rotten Tomatoes, the film holds an approval rating of 88%, based on 73 reviews, and an average rating of 7.17/10. The website's critical consensus reads, "Cargo takes a refreshingly character-driven approach to the zombie genre that's further distinguished by its Australian setting and Martin Freeman's terrific lead performance." On Metacritic, the film has a weighted average score of 65 out of 100, based on 12 critics, indicating "generally favorable reviews". The film has been described as a tribute to the 2009 filmThe Road. In a positive review, Brian Tallerico of RogerEbert.com stated he believed George A. Romero would have enjoyed the film. Clark Collins of Entertainment Weekly gave the film a 'B', saying: "The Australian setting brings a fresh, and epic, quality to this now done-to-death genre". However, Frank Scheck of The Hollywood Reporter criticized the film for being "unlikely to satisfy either viewers looking for serious-minded fare or horror fans looking for genuine frights", but praised Freeman's "quietly intense" performance.
