It began in 2018 when emergency services received a call saying a teenager was walking down a residential Broome street with a gun.
Tour guide Wil Thomas said the call was taken seriously.
"Someone called the police and said 'There's a boy on Reid Road with a machine gun'," he said.
"I think there was more than one police officer in attendance, and they were heavily armed from what I hear.
"Picture Rambo walking through the jungle with a belt of 762-calibre bullets draped over his shoulder and that great big gun in his hand — that's pretty much what it is."
The gun seized by police was real and massive, but it wasn't about to harm anyone.
"They weren't to know it was a 30-calibre World War II relic that was never going to fire again," Mr Thomas said.
It turns out the teen and his friends had stumbled across a piece of history while trying to recover an old boat in the mangroves near the centre of Broome.
"After a particularly fierce easterly wind had blown all night, the barrel of this Colt MG40 was sticking out of the sand," Mr Thomas said.
"One of the boys pulled it out, and there began this whole saga of the machine gun."
Broome air raid
Broome has the tragic title of being the site of Australia's second deadliest wartime attack on the mainland, after the bombing of Darwin.
The exact number of people killed was confounded by the desperate scramble of refugees escaping the Japanese invasion of the Dutch East Indies.
But at least 80 people died in Broome on March 3, 1942, when Japanese fighters strafed the airport and flying boats moored in Roebuck Bay.
Michael Lake from the Broome Museum says the horror of the day, which included the deaths of at least 20 children, remains an important part of Broome's identity.
"Each year the community commemorates the first air raid, bearing in mind that there were three subsequent air raids after that," he said.
"And every fifth year it is what we call a significant commemoration where members of the diplomatic community join the locals to remember those who were lost on that day."
Hunting the gun
As soon as the Broome Museum learned of the machine gun's discovery, it was identified as an important part of Broome's WWII history.
"We have a very iconic picture from shortly after the raid, of guns that have obviously been salvaged from the various aeroplane wrecks," Mr Lake said.
"It shows a salvaged Browning 303 machine gun being prepared for use by the local defence volunteers."
When museum staff contacted police they were told that the gun first had to go to the local Norforce Army Reserve Regiment, but once it was confirmed as a relic it would likely be able to join the museum's collection.
But weeks turned into months and then years.
Conflicting stories emerged that the old machine gun had been sent to Darwin or to Fremantle south of Perth.
But as staff moved on from both the local police station and the Norforce Regiment, four years later the gun was lost to the Broome community again.
Found again
ABC inquiries to museums in Darwin turned up a false lead.
Yes, there had been arrangements to send a historic machine gun from Broome years ago, but no, it had never arrived.
A more promising result came from the Army Museum of Western Australia in Fremantle.
They had a "heavily rusted" machine gun from Broome that fit the description.
But none of the staff had been at the museum for longer than three years, and they could only say the gun arrived at the museum before they had.
But within a few days, a defence force spokesperson was able to confirm that the machine gun in Fremantle had arrived in 2020 after being stored since 2018 by Norforce.
The rediscovery also came with the suggestion that if the Broome Museum requested to take possession of the weapon, this would likely be possible.
The news has rekindled Broome Museum's desire to add the gun to its display.
"Now that we're aware that it is in the Army Museum, I'm sure that the committee will definitely make a move to sort of say, 'Could we please have it back in Broome where it has its historical roots?''" Mr Lake said.
Another machine gun pulled out of Broome's Roebuck Bay was painstakingly restored and revealed it had jammed when a shell exploded in the breach, adding another element to the drama of what happened when the Japanese fatefully attacked Australia's north.
Mr Lake hopes a similar restoration will provide more insights into Broome's tragic WWII history.
"Every object has got a story, it's just finding that story and working it up."