It began nearly a month ago when a 13-year-old Papatoetoe High School student complained of achy muscles.
She and her mother had gone from their South Auckland home to Taranaki for a short break over Waitangi weekend.
They went to popular local landmarks with their hosts, including spending a day ranging around Egmont National Park.
So when the Year 9 student - dubbed case A by health authorities - felt achy and tired a few days later, she put it down to a vigorous weekend in the outdoors.
Unbeknownst to her and her mum, known as case B, a laundry worker at airline catering company LSG Sky Chefs, the pair were the first cases in the current Valentine's Day community cluster that has so far seen 15 South Auckland residents become infected with Covid-19.
With a new high school term getting underway, the first weeks shortened by public holidays and staggered start days, Papatoetoe High School principal Vaughan Couillault said the teen went to school just one day that week when she would have been infectious. After taking the family break, she did not return to class before going to the doctor with her mum.
However, in that brief window at the large South Auckland school, a classmate and another senior student contracted the virus, and subsequently infected their families.
Her self-employed tradie dad, a man in his 40s known as case C, also tested positive, with health authorities describing him as asymptomatic. Just one person in the household of four escaped infection.
Health officials still don't know how the mother or daughter picked up the virus, identified as the highly contagious UK B.1.1.7 strain, or how one of four infected pupils came into contact with the junior girl at the school.
The second family to test positive happened just days later.
On February 16, case D, a female classmate of the infected teen, was found to be infected after a mass testing blitz of pupils and staff.
A day later her brother, a year 12 student at the school, case E and her mum, case F, tested positive.
By week's end a man in his 40s, case G and a girl in her teens, case H, would test positive and everyone in that household would be in quarantine.
However, at some point a member of this second household, despite being under strict orders to self-isolate for 14 days, came into contact with case N, a woman who would pass the virus onto her 21-year-old student son, case M, and who subsequently exposed potentially thousands of people across South Auckland to the virus.
The initial mystery surrounding the student's surprise infection was a main factor in the Government raising the alert level settings for the country, and putting Auckland into lockdown.
The third Papatoetoe family to test positive for Covid, a household of six, was announced a few days later.
Those sick with Covid included a Year 10 pupil at Papatoetoe High School, case I, her older teenage sister, case J, who worked at Kmart and case K, their baby sister.
This infection, which was confirmed on February 23, stumped school leadership and health officials with no obvious connection to the two girls in junior classes at the school.
Then on Friday it was revealed another female member of the household, case L, had tested positive in quarantine. However, she had worked long shifts at KFC Botany in the days prior to being shifted into quarantine, with the fast-food restaurant becoming a location of interest.
Another member of the household, case O, was announced yesterday. As she was already in quarantine during her infectious period, health authorities deem there to be no risk to the public.
The fourth family in the outbreak includes cases M and N that came to light on Saturday. With no obvious link to the first cases nearly two weeks earlier, thousands across South Auckland who attended the Manukau Institute of Technology, a gym and eateries were now potentially exposed to the virus.
While there was a Papatoetoe High School student living in the house with four others, that person had tested negative three times and was asymptomatic.
Case N, the mother of the digital technologies student aged in her 40s, tested positive despite being asymptomatic. Three others returned negative tests and health authorities said all family members were isolating.
Yesterday, health officials confirmed a genomic match between household four and two.
This morning, Prime Minister Jacinda Ardern revealed there had been contact between the two families during a period of self-isolation, which was only revealed after further interviews as health workers tried to establish a link.
The latest case to emerge at the weekend is case O, a household contact of family three. This person was already in quarantine when they become symptomatic, having relocated to Jet Park quarantine facility on February 23 as a precautionary measure.
This afternoon, Ardern revealed the two mothers in the families went for a walk together when the first family was meant to be isolated.
As the second family didn't disclose they had contact with the most recent cases while in lockdown it took longer to find the chain of transmission.
It was also revealed that Case M, the 21-year-old from family four, was in breach when he went to a gym in Papatoetoe after getting a coronavirus test.
Ardern said the 21-year-old had come through managed isolation so had been through "a two-week period of propaganda" when the message about the dangers of Covid was drummed into them - so he should have known to isolate after getting a test.