Injun Joe and Doctor Robinson

The relationship between Injun Joe and Doctor Robinson is one of the novel's most consequential antagonistic pairings, a collision of professional necessity and long-nurtured personal hatred that ends in murder. The doctor, a young professional, hires the two grave-robbers, Injun Joe and Muff Potter, to exhume a body for medical purposes, but the transaction is poisoned by a history of humiliation and resentment that Joe has carried for five years. Their encounter in the graveyard at midnight transforms a grisly but routine act of body-snatching into a scene of violent retribution, and the doctor's death becomes the crime around which the entire middle section of the book revolves.

Origins of the Conflict

The roots of the enmity lie in an incident that occurred five years before the novel's main action. Injun Joe, coming to the doctor's father's kitchen one night to ask for something to eat, was driven away by the younger Doctor Robinson, who declared that Joe "warn't there for any good." When Joe swore he would get even "if it took a hundred years," the doctor's father had him jailed as a vagrant. This double humiliation—being turned away hungry and then imprisoned—festered in Joe, who explicitly invokes his "Injun blood" as the reason he could not forget the injury. The doctor, for his part, appears to have dismissed the incident entirely, treating Joe as a mere hired hand when he engages him for the grave-robbing job.

The Graveyard Confrontation

The fatal encounter occurs in the graveyard, where the three men have come to exhume the body of Hoss Williams. After the corpse is dug up and placed on a barrow, Potter demands additional payment beyond the advance already given. Injun Joe immediately seconds this demand, then turns on the doctor directly, reminding him of the old grievance and threatening him with his fist. The doctor strikes out, knocking Joe to the ground. Potter grapples with the doctor, and during the struggle, the doctor frees himself and fells Potter with a heavy headboard. In that instant, Injun Joe seizes Potter's dropped knife and drives it "to the hilt" into the young man's chest. The doctor reels, falls partly upon Potter, and dies after a few gasps, his blood flooding his assailant.

Aftermath and the Settled Score

Standing over the two forms, Injun Joe mutters, "That score is settled — damn you," then robs the body. He places the fatal knife in the unconscious Potter's hand, framing him for the murder. When Potter revives, confused and believing himself guilty, Joe coolly lies, describing a version of events in which Potter, stunned by the headboard blow, snatched the knife and stabbed the doctor. Joe's calm, repeated statements under oath at the inquest convince the town of Potter's guilt and confirm for the two boy witnesses, Tom Sawyer and Huckleberry Finn, that Joe has "sold himself to Satan." The doctor's murder thus becomes the engine of the novel's moral drama: Tom and Huck are bound by a blood oath to silence, Potter faces the gallows, and Injun Joe remains at large, his thirst for revenge not yet slaked. The relationship ends with the doctor dead and Joe's hatred, far from exhausted, redirected toward other targets, most notably the Widow Douglas, whose husband had once had Joe horsewhipped.