Scores of crew members on the Ruby Princess celebrated with a party on the day it docked in Sydney, unaware of the public health disaster that was about to happen.
It was 19 March - about a week after the World Health Organisation had declared a global coronavirus pandemic - and on the ship, dancers and musicians put on a show for everyone from the galley hands to the uniformed officers.
Sydney turned on a spectacular afternoon, and while the cruise had been cut short because international borders were closing, the impression among some crew members was that the ship was free of Covid-19 after NSW Health allowed the nearly 2700 passengers to disembark that morning.
Two former crew members who attended the party have told the ABC's 7.30 programme the mood on board was ecstatic.
New Zealander Chris Harris had been a trumpet player in the ship's orchestra since December last year. Formerly a musician in the New Zealand Army, he had worked on cruise ships for many years.
On the day of the party he played in the band, which performed songs such as Down Under and YMCA.
"When we left on March 19, as far as we were aware, we were a healthy ship," he said.
The "sail away" party would normally be reserved for passengers, but with the ship free of guests, the crew were treated to a special event.
Another crew member at the party was Byron Sodani, a fitness instructor who boarded the ship in January.
"A party without passengers - it never happens," Sodani said.
"When we normally sail away there's a dance and music, there's a singer, there's some cocktails going on, just welcoming the guests.
"And that was for us."
But the next day, NSW Health would confirm that three passengers who had already disembarked and one crew member still on board had Covid-19.
Now more than six weeks later, almost two dozen passengers have died and more than 600 passengers have tested positive to Covid-19. Two hundred crew members tested positive.
At the party the crew were allowed to mingle despite the pandemic.
"People weren't too concerned about it," Harris said.
"We were aware of the social distancing but in our minds, we were thinking the ship is healthy, nobody's got the coronavirus, so we don't need to worry."
Sodani believed crew members' health was put at risk.
"We thought we had a clean ship and the idea of Covid-19 was just outside," he said.
"Because why would you let us do a party together?
"When it comes to health, I feel like we have all been put in danger here."
The Ruby Princess has now left Australian waters with some crew remaining on board. Many have since been repatriated after spending more than two weeks in Wollongong where the Ruby Princess was quarantined.
Harris made it off the ship and is currently in quarantine in an Auckland hotel.
Sodani has returned to his home in Italy. "It's good to be home and it's good to just feel a little bit safer," he said.
The ship's operator, Princess Cruises, declined requests for an interview, but a company spokesperson said "the health of our crew is an extremely high priority".
"This is why we did not agree to Ruby Princess initially leaving Australian waters because it was important for the ship to remain for access to health services should they be needed," he said.
A Special Commission of Inquiry into the Ruby Princess continues this week.
Customs is leading an investigation into the ship's visit to New Zealand, which is responsible for a cluster of almost two dozen Covid-19 cases in this country.