A woman holds up an image of late prosecutor Alberto Nisman in Buenos Aires on Jan. 29. Nisman was found dead four days after he announced he would charge Argentina’s president with helping to cover up the culprits in a van bombing. (Marcos Brindicci/Reuters)

Moments before Argentine prosecutor Alberto Nisman presented his findings in the case that had come to define his life, and just days before his violent death would horrify the nation, he texted a group of friends a solemn message.

“What I am about to do now had already been decided awhile ago, and I am prepared for this,” he wrote. “I do it convinced that it is not going to be easy. Completely the opposite. But sooner or later, the truth will triumph.”

Later that day, Jan. 14, Nisman announced that he was filing criminal charges against the president of Argentina, Cristina Fernández de Kirchner, for conspiring with Iran to cover up the culprits in the worst terrorist attack in the country’s history. The 1994 van bombing of the Argentine Israelite Mutual Association (AMIA), a downtown community center, killed 85 people. It has been, over most of the past two decades, Nisman’s only case. For the athletic, handsome 51-year-old lawyer from a middle-class Jewish family, the professional challenge would grow into an obsession.

His quest for answers took him around the world and into the confidences of politicians and spies. It alienated colleagues, strained his family and won him a 10-person federal police security detail. As Carlos Donoso Castex, the head of the country’s prosecutors’ association, saw it: “The case, for him, was his life.”

On Jan. 18, four days after his announcement, police found Nisman slumped on the floor of his apartment bathroom in a pool of his own blood, shot through the head. A black, .22-caliber Bersa Thunder pistol lay by his side. It was suicide — or a murder masterfully made to look like one.

Argentinean President Cristina Fernandez de Kirchner speaks in Buenos Aires on Jan. 30. Fernandez has called the allegations against her “absurd.” (David Fernández/European Pressphoto Agency)

“Ah, and in case anyone thinks I’ve gone crazy, it’s nothing like that,” he had signed off to his friends. “I’m better than ever.”

Compulsive and secretive

Claudio Rabinovitch read the text message and was furious. He had known Nisman since they were teenage tennis players in public schools. They studied law together at the University of Buenos Aires. They vacationed in the Brazilian beach town of Florianopolis, where Nisman, then clerking for a judge, kept making phone calls about a case instead of relaxing in the sun.

For two years, Rabinovitch had worked part time as Nisman’s press adviser on the prosecutorial team investigating the AMIA bombing, and yet this was the first he was hearing of this blockbuster revelation. He’d had enough of Nisman’s secrecy. Rabinovitch told his wife he wanted to resign.

Nisman could be like that, his other friends and colleagues knew. Compulsive about ordering and protecting information, confiding in certain people, excluding others. Diego Lagomarsino, a computer technician on Nisman’s team, would later tell his lawyer a story about Nisman once stepping away for privacy when he took a cellphone call. When he came back, Lagomarsino casually tossed down the car magazine he’d been flipping through. Nisman picked up the magazine and aligned it on the table just as it had been before.

“He was terribly obsessive, hyperkinetic. He always thought about his work,” recalled Susana Ciruzzi, who, like Nisman, taught criminal law classes at the University of Buenos Aires. “He was very sure of himself and would defend his ideas tooth and nail.”

Nisman had joined the AMIA investigation in 1997, as a subordinate to two other prosecutors. The trial started four years later but got badly bungled — there was video of a judge offering a suspect $400,000 to testify — and all charges were thrown out for lack of evidence.

Ten years after the bombing and the botched trial, President Néstor Kirchner’s administration created a new investigative unit within the attorney general’s office to focus solely on the case and chose Nisman to lead it. The group grew to an estimated 60 to 80 people — exceptionally large compared with a normal prosecutorial team of 10 — and had an ample budget, from which Nisman took a salary of about $140,000 a year.

In 2006, Nisman concluded that top Iranian officials ordered and financed both the AMIA bombing and an attack two years earlier on the Israeli Embassy in Buenos Aires that killed 29 people. The Lebanese-based Hezbollah militia, he argued, helped carry them out. Nisman filed charges against top Iranian officials, including Iran’s former president Ali Akbar Hashemi Rafsanjani; its defense minister, Gen. Ahmad Vahidi; and former Revolutionary Guard commander Mohsen Rezaei. Interpol issued arrest warrants the following year. Iranian officials consistently denied any involvement and refused extraditions.

Nisman was becoming an expert on Iran and terrorism at a time when the United States was fiercely interested in the same topics. He believed that Iran was exporting its revolutionary ideology to Latin America and that Hezbollah was active in the smugglers’ paradise of the “triple border” region where Argentina, Brazil and Paraguay come together. He would regularly meet with American diplomats, law enforcement officers and intelligence officials.

To his shock, in January 2013, the Argentine government signed a memorandum of understanding with Iran to create a “truth commission” to jointly investigate the case. Fernández, the president, characterized it as a breakthrough in the stalled investigation that would allow Argentine investigators to finally have access to Iranian testimony. Nisman considered it unconstitutional and a betrayal of the country and his work, his colleagues recalled.

“When we met the first time after the memorandum, he was furious,” recalled Gustavo Perednik, a friend of Nisman’s who wrote a book about him. “It demanded him to give information to the perpetrators.”

The Iranian parliament never ratified the agreement. Argentina’s National Congress did, but an appeals court blocked the agreement, and it never went into effect. Four months after the memorandum, Nisman released a 502-page report asserting that Iranian agents were setting up secret spy bases across Latin America “designed to sponsor, foster and execute terrorist attacks.”

“These are sleeper cells,” he said at the time of the report’s release. “Sometimes they die having never received the order to attack.”

The investigation became central to his identity. For his Whats­app profile picture, Nisman used not his face, but a slogan: “Keep calm and we don’t negotiate with terrorism.”

Death threats

After Néstor Kirchner’s death and his wife’s outreach to Iran, Nisman told friends that he was losing support. Iran called him a “Zionist,” even though he wasn’t particularly religious or active in the Jewish community in Buenos Aires. His boss, Attorney General Alejandra Gils Carbó, prevented him from accepting an invitation to testify before the U.S. Congress in 2013. He received death threats — in one case, a voice-mail message that frightened his daughters — and a security detail began following him around in Ford Fiestas.

He got divorced from a federal judge, Sandra Arroyo Salgado, and moved into a two-bedroom apartment in the posh riverfront neighborhood of Puerto Madero, on the 13th floor of Le Parc tower, which overlooked a Mercedes-Benz dealership. His two daughters and beloved golden retriever, Tango, stayed with his ex-wife.

The work took its toll on him, but his friends never considered him to be depressed. For several months last year, he met a personal trainer, Daniel Tangona, at 4:30 p.m. every Thursday at the gym in his building for an hour-long session of stretching and cycling to help ease the pain in his lower back. Nisman followed a nutritional routine: fruits and vegetables, sushi and water, in small quantities several times a day. He would turn off his cellphone and focus intently on his workouts.

“He was obsessive about the movements and the technique,” Tangona said. “I told him he had lots of accumulated tension, and he should practice some boxing to get rid of it. He liked that suggestion.”

Nisman had done an Art of Living course, a meditation class that focused on a positive life philosophy. “He told me, ‘We’re 50, but we’re both healthy. We need to take advantage of that,’ ” Rabinovitch recalled. “He had a very positive outlook.”

The case had “changed his life,” Perednik said. “He became a fighter for justice. And no one was going to stop him.”

Perplexed colleagues

“Do you have a gun?”

That was the request Nisman put to Lagomarsino, his pale, lanky 38-year-old IT assistant, on the afternoon of Saturday, Jan. 17. Since bringing charges against the president, Nisman had been working diligently to prepare for his testimony in a closed session of Congress the following Monday, even as his government pilloried him publicly for his claims.

Nisman’s colleagues were perplexed by his decision to file the complaint when he did. Several months before, he had told Marta Nercellas, a former lawyer for AMIA, that he wanted to wait until after Fernández left office because otherwise “it would look like political interference,” she recalled.

But he claimed he was breaking off a European trip — forgoing a planned ski vacation in Andorra with his 15-year-old daughter, Iara — to rush home. Some say his mother was sick; others say he was worried that Gils Carbó, the attorney general, planned to take him off the case. The month before, Fernández had removed a powerful intelligence official, Antonio “Jaime” Stiusso, who worked with Nisman on his nearly 300-page complaint, which included wiretap transcripts of the president’s allies allegedly negotiating a secret deal to absolve the Iranians in return for oil.

Regardless, Nisman was moving ahead. When Rabinovitch visited the apartment Friday afternoon, he found Nisman and an aide, Soledad Castro, “poring over the details.” Rabinovitch decided to postpone his resignation. “Of course you’ll be there with me on Monday,” Nisman told him.

The next afternoon, Nisman texted Waldo Wolff, the vice president of an AMIA-affiliated Jewish organization, a photo of his living room table, covered with documents and yellow highlighters. “He told me he was working,” Wolff said.

But later that afternoon, Nisman called Lagomarsino and asked him to come over. They had known each other for about a decade, according to Lagomarsino’s lawyer, Maximiliano Rusconi. Lagomarsino had started out doing home computer work for Nisman and his wife, then was hired as part of the prosecutorial team. Lagomarsino drove south to Puerto Madero in his Ford Ranger, through the light Argentine summer-vacation traffic, noticing no guards when he parked and rode up in the elevator.

Nisman told him he wanted the gun because he feared for his daughters’ safety and was afraid that some fanatic might attack him for being a traitor to the country. He said he didn’t trust his bodyguards, Lagomarsino told reporters later. Lagomarsino had an old pistol and agreed to go fetch it.

“I regret I said yes,” Lagomarsino said.

Suicide or murder?

Nisman’s body was found next to Lagomarsino’s gun the next evening, more than 24 hours after the visit. Forensic tests have shown that no gun residue dusted Nisman’s hands. The only DNA found on the gun and his clothes has been his. His ex-wife, other relatives, friends and colleagues all believe he was murdered; some blame the government. Fernández, who initially suggested suicide and then pronounced it murder, has fingered Lagomarsino, implying he was part of a rogue spy plot to manipulate Nisman. Lagomarsino denies the charge.

As protests erupted over the scandal, Fernández said she would dissolve the nation’s spy agency and called Nisman’s accusations against her “absurd.” No suspects have been charged in the death.

Nisman is credited with not only advancing, but also systematically organizing, a labyrinthine two-decade investigation. Due to his mastery of the details, his renowned memory and his relentlessness, the case, in some ways, survived inside his mind. And with him, the search for the perpetrators of one of the hemisphere’s worst terrorist attacks, and any explanation of his own fate, may also have perished.