LitCharts assigns a color and icon to each theme in The Dry, which you can use to track the themes throughout the work.
The Human Cost of Climate Change
Justice
Urban vs. Rural
Friendship
Summary
Analysis
Barnes wonders how Whitlam got to the Hadler farm if surveillance footage shows his car at the school the whole time. Falk realizes that the horizontal lines in Luke’s ute must be from bicycle tires—Whitlam rode must’ve ridden his bike over and then flagged down Luke in his ute to make him stop. Wearing gloves, he hit Luke in the head with a rock, then he used his Remington ammo to shoot Luke with Luke’s own shotgun.
After the big reveal of the killer, the subsequent chapters wrap up some of the other little mysteries from the novel, like the marks on Luke’s ute. Despite the care Whitlam took to conceal the murder, he makes a significant error with the brand of shotgun ammo he uses (perhaps once again reflecting his city background and resultant lack of knowledge about rural matters like hunting with a shotgun).