Scruffy-haired and heavily tattooed, Jimmy is a courier tangled in a web of trouble, with a staggering A$15,000 debt to Banos, the menacing owner of a car repair shop where he once worked. Banos has issued a strict ultimatum: Jimmy must repay him by 5 o'clock that day or face severe repercussions. Meanwhile, Jimmy's thoughts are consumed by the excitement surrounding a horse race at Ballarat.
In a rush, he picks up his mate Steve, another courier, but being late forces him into a precarious situation—he must also pick up his pre-teen son Alex. This father-son relationship is strained; Alex respects his father little and openly challenges his authority, complicating an already tense day. Adding to his troubles is Karen, his ex-wife, who incessantly nags him about his responsibilities.
Driving around in his cherished 1968 Ford Fairlane—a car once owned by his father who abandoned the family—Jimmy finally retrieves Alex, who reluctantly gets in the car. As they navigate their day, Jimmy's responsibilities weigh heavily on him. Arriving late at the depot means he has to use the Fairlane for deliveries instead of a company vehicle, which results in Alex tagging along for an adventurous ride through various Melbourne businesses.
After completing the deliveries, the pair stop for lunch at a suburban hotel featuring TAB betting. Here, they meet up with Steve. Driven by desperation, Jimmy borrows a significant amount from him to place a bet on his horse, which miraculously wins. With newfound confidence, he calls Banos to share the good news but quickly succumbs to temptation, risking it all on another bet—resulting in a loss that leaves him in dire straits. In his panic, he turns to Steve for help, but discovering Steve has his own debts only intensifies his despair.
In a final stroke of desperation, Jimmy considers selling the Fairlane, valued at $35,000, but after a moment of reflection, he backs out before completing the deal, driving away with Alex.
Meanwhile, Steve reconnects with Mel, an old friend who operates a small bakery. With her assistance, he finds a way to make some cash by delivering suspicious packages, claiming to Alex that they are merely filled with vitamin C. However, the situation grows tense when Alex inadvertently opens one of the packages, about to put the contents in his mouth when Jimmy rushes back to intervene. This pivotal moment leads to a heartfelt exchange between father and son, helping them reconnect.
In the climactic confrontation with Banos, armed only with a few hundred dollars, Jimmy faces the consequences of his decisions. As Banos's men beat him mercilessly, it appears all hope is lost, but an unexpected change of heart comes from Banos himself, who stops the assault. In a final act of surrender, Jimmy relinquishes the Fairlane to Banos and bicycles back to Karen's house, with Alex joyously perched on the handlebars. As night falls, when asked by his mother how the day went, Alex exuberantly replies, “It was the best day ever.”
