One of the few things we know about the end of the comic-strip writer Héctor Germán Oesterheld’s life is that he was allowed to smoke a cigarette on Christmas Eve in 1977. Argentina’s National Commission on the Disappearance of Persons, or conadep, issued a report in 1984 containing that detail. The report quotes Eduardo Arias, a psychologist detained with Oesterheld:

The guards gave us permission to take off our hoods and smoke a cigarette. They also allowed us to talk to each other for five minutes. Then Héctor said that as he was the oldest he wanted to shake hands with all the prisoners present, one by one. I will never forget that handshake. Héctor Oesterheld was sixty years old when this happened. His physical condition was very bad indeed. I don’t know what happened to him. I was freed in January 1978. He stayed in that place.

Both men were prisoners of the Argentine junta at one of its most notorious facilities, a detention and torture center situated in a police station in the Villa Insuperable neighborhood in the province of Buenos Aires. It was known mainly by its ironic nickname, the Sheraton. Oesterheld and three of his four daughters were among los desaparecidos, “the disappeared,” those people who were kidnapped and almost certainly murdered by the regime; the fourth died during a botched abduction.

For most of his life, Oesterheld was a beloved writer of pulp adventures—Westerns, stories of alien invasion, tales of the battlefield in the Second World War—that often bend or break genre rules. When Oesterheld departed from convention, it was to tweak reigning pieties. His cowboys are villains who oppress courageous Indians. His war stories privilege moral ambiguity over daring exploits. When his aliens invade an imaginary Argentina, feckless governments abandon a persecuted citizenry, who have to resist the invaders as guerrillas. His work reflects a desperate search for heroism, at first in adventure stories and then among real-world figures like Eva Perón and Che Guevara, who star in his comics less as historical figures than as avatars of his passionate leftism.

In Oesterheld’s early stories, his political views are disguised, at least in part out of necessity. He addresses his country’s problems elliptically, and in narrative forms that would have been familiar to young people browsing newsstands stocked with exciting stories, but his outrage at the status quo is unmistakable. His boldness in the face of Argentina’s parade of violent and censorious dictators earned him a devoted following, but when, late in life, he became the kind of guerrilla fighter he admired, the government with which he had sparred so effectively in his stories crushed him with no more difficulty than it had thousands of others. In his memory, other writers continued to produce comics about his characters, including fictional versions of himself, granting him a posthumous career not as a pulp comic-book hero come to life but as a real-life guerrilla who became a comic-book hero.