As Castresana looked deeper into Rosenberg’s life, he began to see a tormented soul—“someone like Raskolnikov.” After the death of the woman he loved, Rosenberg wrote to a friend that he felt as if he were “disintegrating, little by little.” He initially tried to do what he had always done: find justice through the law. Based on the intelligence he had gathered—primarily from the legendary spy Mendizábal but also from other sources—he was convinced that the government had killed Marjorie and her father. But, as a lawyer, Rosenberg knew that this intelligence was not strong enough to stand up in court. And Mendizábal warned Rosenberg that it would be futile to fight the President, the First Lady, and Alejos. In a country where crimes were virtually never punished, Castresana says, Rosenberg felt powerless. In a meeting at his law firm, Rosenberg complained, “There is no justice in Guatemala.” And so, Castresana theorized, Rosenberg had set his plot in motion.

In hindsight, Rosenberg’s actions in his final days made it evident that he was not trying to evade death but, rather, was preparing for it. He had his will drawn up; he bought two adjoining plots in a cemetery, one for himself and one for Marjorie; he gave away family heirlooms. He had then constructed a counterfeit reality, believing, however perversely, that it was the only way that the guilty parties would ever go to jail. And he employed the very methods—hit men, misdirection, stagecraft—that, in the past, had been the province of corrupt states and intelligence outfits. Rodrigo Rosenberg had democratized the art of political murder.

After solving the mystery of Rosenberg’s assassination, Castresana was overcome with panic, instead of relief. He thought that the plot was so incredible—perhaps the most bizarre in the annals of political conspiracy—that everyone would think that he was weaving yet another fraudulent narrative, in order to protect the government. For days, he could not sleep, and paced endlessly around the compound. “It will be my professional grave,” he muttered to himself. “But we cannot change the reality.”

In December, CICIG issued arrest warrants for the Valdés Paiz brothers. They went into hiding, and were not apprehended for several months. The ten members of the hit squad were eventually convicted. The Valdés Paiz brothers initially acknowledged their involvement in the plot, according to authorities, but they now maintain their innocence. Their case is still pending.

Castresana prepared to share his findings in a televised national address on January 12, 2010. The day before the broadcast, he met with Rosenberg’s son Eduardo. Many members of Rosenberg’s family could not accept what had happened: the truth, for all its power, is merciless. But Eduardo seemed ready to confront reality. He later told me that he had been forced to face “a lot of dark truths.” In the meeting with Castresana, he made one request: if Castresana believed that his father had been trying, even if mistakenly, to help his country, then he should say so at the press conference.

During his address, Castresana, to the surprise of many viewers, said of Rosenberg, “He was an honorable person.” He added, “He wanted to open up a Pandora’s box that would change the country.”

In the palace, President Colom, the First Lady, Gustavo Alejos, and Roberto Izurieta watched the address on television. Just before the broadcast, Izurieta met with Colom to prepare an official response. Izurieta asked the President, “So who did it?”

Colom said, “You’re not going to believe it, but I don’t know.”

As Castresana built toward his shocking conclusions—which he described as “the truth, the whole truth, and nothing but the truth”—the President held hands with the First Lady. Alejos, who told me that the investigation had “cleared my name for my family and my children,” began to cry. Izurieta whispered to himself, “Oh, my God.”

Though President Colom and others who had been in the war room trusted Castresana’s conclusion that Rosenberg had plotted his own death, many of them still privately believed that there remained another shrouded part of the story—a conspiracy within a conspiracy. They felt that Rosenberg alone could not have pulled off such an intricate deception, and that he must have been abetted by García, the talk-show host, and Mendizábal, the spy, both of whom had reasons for wanting to bring down the government.

Castresana told me he believed that García and Mendizábal had tried to exploit the mysterious circumstances of Rosenberg’s death. “I don’t know if they were aware of the intention of Rosenberg” to kill himself, he said. “But they were preparing some kind of coup.” CICIG’s investigation eventually found a witness who said that García had met with Rosenberg, and encouraged him in his plans to commit suicide and release the video, saying, “Do it for your country.” Castresana told me that García likely helped “induce” Rosenberg’s suicidal act.

The conspiracy-within-a-conspiracy may have reached the highest levels of the government. Mendizábal told me that, in the days leading up to Rosenberg’s death, he had detected, in his intelligence dossiers, growing divisions between President Colom and Vice-President Espada. “This is where I say that my reports are helping me quite a lot,” Mendizábal explained. “I’m beginning to see that the Vice-President and the President are having a lot of friction, because the Vice-President would like to be President.” A friend of Mendizábal’s told CICIG that, about a week before the assassination, he had met with the Vice-President to inform him about Rosenberg’s investigation into the Musa killings, which had the power to topple Colom’s Presidency. Mendizábal told me that the friend had asked the Vice-President, “ ‘Do you think you are in a position to take over?’ And his answer was yes.”

Vice-President Espada has emphatically denied that such a meeting ever occurred, saying that he had no “direct or indirect contact” with Rosenberg or anyone close to him before the murder. García, for his part, has called allegations that he was complicit in Rosenberg’s plot “absurd, baseless, and reprehensible.” Mendizábal’s statements have been more calibrated. He told a reporter, “I was not the instigator. I did what I had to do, and I have no regrets.” He showed me the metal plate, inscribed with “ON,” that he had found by the Rosenberg crime scene. He turned it upside down, so that it said “NO.” “There are always two ways to interpret anything,” he said.

Mendizábal had already begun to construct a counter-scenario to subvert CICIG’s theory of Rosenberg’s death. He said that Rosenberg had not set out that morning to kill himself; rather, he was attempting to collect information on who murdered the Musas—evidence that Rosenberg must have paid forty thousand dollars to obtain. When the Musas’ killers learned of his plans, he was double-crossed and killed. As Mendizábal spoke to me with conviction, taking some of the verifiable facts and rearranging them, I began to picture Rosenberg on his bicycle, innocently pedalling through the city, hoping to obtain the final piece of his puzzle. The most effective counterfeit realities are those which provide what only conspirators seem to have: a perfectly coherent plot.

This time, though, the truth was more powerful than fiction. After Castresana’s meticulous presentation, the director of El Periódico, who had once written how absurd it would be to imagine that Rosenberg “immolated himself, kamikaze style,” called CICIG’s research “masterly,” and said, “I can only humbly surrender to the evidence.” U.S. Ambassador McFarland told me that the CICIG probe helped preserve “Guatemala’s stability and democracy,” and demonstrated that it was possible to “get to the bottom of things.” People beseeched Castresana, who was hailed as Guatemala’s Eliot Ness, to run for President.