TORPEDOES slammed into the hull of a ship 80 years ago today, in total secrecy.
The families of those who died are still feeling the shockwaves.
Many plan to gather at commemoration services across Australia this morning.
They will remember more than 1000 people thought to have gone down on Japanese ship the Montevideo Maru.
Among them is Lois Newman, who will reflect on Australia's worst wartime naval disaster at a service hosted by Bendigo's RSL branch.
Her uncle Leonard Wall was among those believed to have been locked below deck when the torpedoes struck.
"I still cry when I talk about it," she said.
Lois will be among those planning to gather to reflect in a peaceful yard out the back of Bendigo's RSL to remember.
Leonard was among those captured at Rabaul, a township in a volcano-pocked corner of modern-day Papua New Guinea.
Japanese forces had just swept through in lightning attacks over the 1942 new year.
Rabaul's ill-equipped and outgunned soldiers were overwhelmed.
Leonard was not lucky enough to escape in a desperate jungle hike once his commander ordered every man for himself.
But he avoided some dangers, Lois said, including a massacre of 160 of his comrades in a plantation that February.
Lois grew up in a family where people refused to talk about World War Two.
She sometimes asked her grandparents about a picture that hung over their home's fireplace.
They only told her that the handsome man photographed wearing a military uniform had died in the war.
The silence was so deafening that years later, when Lois' husband found some information on the internet, her mother at first refused to believe her loved one was linked to the Montevideo Maru.
Lois and a network of 150 family members now diligently piece together the stories of the military men and civilians connected to the fall of Rabaul.
They feel sorry for so many people caught up in its aftermath, including the submariners onboard the USS Sturgeon.
They were the ones who fired their torpedoes on the Montevideo Maru.
"Those poor men must have felt horrid," Lois said.
The submariners would have had no indication that the ship they had tracked meticulously was carrying their allies, she said.
Every prisoner on board appears to have been locked below deck.
There are no indications Japanese sailors displayed signs that would have indicated any Allied soldiers or civilians were onboard.
Japanese authorities failed to report the losses to Allied forces during the war, though Australia had strong suspicions.
Australia only let families know of their losses in the months after the war ended.
And even then, key details could have been lost forever if not for the tenacity of Major Harold Williams, the man Australia tasked with finding answers in the rubble of post-war Tokyo.
His reports back to his superiors paint a picture of record offices destroyed by allied bombs, of panicked soldiers burning caches of documents and bureaucrats dragging their feet.
Harold spent the end of 1945 begging, cajoling and demanding the trust of people who months earlier had been sworn enemies.
Some were clearly incompetent, some feared war crime allegations and others simply did not have the facts to give.
Harold was twice forced to rebuke no less a figure than a Japanese general he suspected of bending the truth in memorandums.
"After I had made my views entirely clear, [the general] stated that he would correct his memorandum, which he thereupon asked me to return," he told his superiors in one report preserved by the National Archives of Australia.
"I informed him that I could not return it, but that I would await a correction."
Eventually, Harold was able to get an account that he felt he could rely on.
He reported that the Montevideo Maru was torpedoed about 3am on July 1, 1942.
The ship sank within 10 minutes.
It disappeared so fast that the only survivors were those crew and Japanese naval guard members on the bridge and main deck.
Of more than 1200 people on board, 20 crew and Japanese naval guard members got into lifeboats.
They landed on an island in the Philippines and battled their way through the jungle (and sometimes literally against hostile locals) to safety.
"Some were wounded and all suffered greatly from hunger, exhaustion and privation," Harold told his superiors.
That account remains the one most widely accepted today, though it has its critics.
Some people suspect the Montevideo Maru story was concocted by Japanese officials to hide war crimes committed at Rabaul.
But most people, Lois included, believe the ship exists, and that enough evidence has been gathered over the years to show Australian soldiers really were on board when it sank.
Lois says Harold was a man doggedly determined to get answers, which she bases both on his reputation and his investigations in Tokyo.
Harold had also been able to cross-check the final account of what had happened against scraps of information he had gleaned first-hand from freed war prisoners making their way home through the Philippines in 1945.
One day, someone might dive on the site where the Montevideo Maru lies to see if Harold was right.
That would pose a technical challenge. The ship is down deeper than the Titanic, in an area prone to strong tides and volcanic activity.
Still, people have asked family members if that is something they would want.
Most have not, Lois said.
"It's a war grave. Why would you want to dive on it?" Lois said.
"I don't think that will ever happen."
This story is the latest in the Bendigo Advertiser's semi-regular history series, entitled 'WHAT HAPPENED?'
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