The San Juan was not a young vessel. Built in West Germany by Thyssen Nordseewerke, she was launched in 1983 and had served the Argentine Navy since 1985, completing a mid-life overhaul between 2008 and 2013 that replaced every battery cell. But a submarine is more than steel, and the forty-four aboard were not a statistic. Among them was Eliana Krawczyk, the first woman to qualify as a submarine officer in Argentina's navy and, on that patrol, its third-highest-ranking officer and the only woman in the hull. They had families waiting in port towns and inland cities, families who would soon gather at the naval base in Mar del Plata and refuse to leave.

When the silence was announced on 17 November, the world responded. More than 4,000 personnel from thirteen countries joined the hunt, scouring roughly 500,000 square kilometers of ocean, an area the size of Spain. American P-8 Poseidons dropped sonar buoys; Brazilian and British ships steamed south; a Russian survey aircraft was expected. Every lead became a heartbeat. A satellite phone call that turned out to be nothing. A sound on the hull that analysts decided was biological. A heat signature, three flares glimpsed in the dark. Each was chased at full speed and each dissolved. All the while, the boat carried oxygen for at most seven to ten days submerged, and storms with eight-meter waves kept beating the search back. The families waited at the base, where the navy had brought in counselors, as the clock ran down.

The answer, it turned out, had been recorded on the first day. Listening stations run by the nuclear-test-ban organization CTBTO, on faraway Ascension Island and the Crozet Islands, had captured a single sharp event in the South Atlantic about three hours after the San Juan's last contact, an acoustic signature consistent with an implosion. The data did not reach Argentina until 22 November. By 30 November, fifteen days after the boat vanished, the navy formally ended the rescue and began searching only for the wreck. It was the gentlest way to say what everyone already feared. For the families, the long ambiguity gave way to a grief that had been delayed but never softened.

Argentina kept searching alone after the international effort wound down, eventually offering a reward of roughly five million dollars. In September 2018 the seabed-survey firm Ocean Infinity took up the hunt on a no-find, no-fee basis, with three navy officers and four crew family members aboard to watch. On 16 November 2018, a year and a day after the submarine was lost, a remotely operated vehicle found her at a depth of 907 meters. The photographs were unsparing: the pressure hull had imploded, the bow, sail, and propellers flung across 8,000 square meters of dark seafloor. The wreck lies far offshore, beyond the reach of any feasible recovery, a grave in the deep where the boat came to rest.

The loss of forty-four crew made this the deadliest submarine disaster since the Chinese boat 361 went down in 2003, and Argentina's worst peacetime naval tragedy since the minesweeper ARA Fournier and her crew of 77 were lost in 1949. The reckoning that followed was bitter. The navy's chief of staff was dismissed within weeks; investigators pored over the boat's maintenance history and its final mission. On 24 October 2021, a monument to the forty-four was unveiled at the entrance to the Mar del Plata Naval Base, where their families had once stood vigil. The sea keeps the San Juan now. The memorial keeps her crew.