Tom talks his way aboard

Outside a roadside restaurant, a man in cheap new clothes and stiff new shoes waits by a red transport truck marked "No Riders". When the driver comes out, the man shames him into a lift — refusing would make him neither a good guy nor his own master. Riding along, the driver probes with casual questions: the callused hands, the new clothes, whether the man's father has been dusted out or tractored off his forty acres. The passenger gives his name, Tom Joad, and grows steadily more irritated by the interrogation. Finally he calls the driver out for it, crushes a grasshopper that lands on the dash, and volunteers everything: four years in McAlester on a seven-year sentence, released early for good behaviour, and the crime was homicide. He gets down at a dirt turning and walks toward his father's place. The driver calls "Luck!" after him.

Tom enters through interrogation rather than description. The "No Riders" sticker is the book's first small tyranny, and Tom's shaming of the driver into defying it previews his refusal to be pushed. Volunteering the homicide rather than concealing it installs the parole as the plot's binding constraint.