A man accused of killing his partner and her child told police she left in a taxi for the airport in 2007 and he never saw her again.
The Crown says Kamal Gyanendra Reddy, 42, fabricated the story because he had murdered Pakeeza Yusuf and her 3-year-old daughter Juwairiyah "Jojo" Kalim.
It's alleged he strangled his partner with an electrical cord before smothering the child in late 2006 or early 2007.
Their remains were found buried under the Takapuna overbridge in October 2014 after a wide-reaching undercover police operation.
The trial, before the High Court at Auckland today, heard from police officers who described how their investigation began in 2013 when the victims' mother and grandmother Mubarak Rojina Banu made a missing-persons complaint.
Detective Amarjeet Kumar, who was originally tasked with finding the duo, said in initial talks with Reddy, he said he had arranged to pay Ms Yusuf and her family $10,000 in return for helping him attain residency in New Zealand.
The defendant reneged on the deal when his work later sponsored him in his residency bid.
Reddy allegedly told him the last time he had seen his partner was when she was getting a taxi to the airport to meet an aunt who was arriving from Australia.
The defendant believed they had then gone to Hamilton, Mr Kumar said.
The case was later passed to the Organised Financial Crime Agency of New Zealand's major crime team, who also interviewed Reddy.
Detective David Sanday said Reddy gave them a similar story about his last contact with Ms Yusuf but mentioned they may have gone to Wellington.
The defendant said everything was "normal" in the relationship at the time.
"There were no arguments and everything was good. I think she was happy because her ex-husband did not know where she was," Reddy said, according to Mr Sanday.
Ms Yusuf was living in Howick at the time of her disappearance and the defendant allegedly told police he would only stay the night at weekends.
"She told me if I got caught living at the house, Winz would withdraw her benefit."
Between April and October 2014, police launched an extensive undercover operation targeting Reddy.
The court will hear through the trial how an undercover officer gained the defendant's trust through a series of "simulated criminal scenarios".
Eventually Reddy made admissions that he had killed the victims and buried their bodies, before unwittingly leading officers to the burial site.
But defence lawyer Jonathan Krebs warned the jury to be critical of the so-called confession.
"I say to you from the outset: it's false, it's a cobbled-together story."
He said his client was effectively groomed by undercover officers to the point where there was "immense pressure" on the 42-year-old to make admissions.
"What if a person didn't commit the crime but knew enough about the crime to give a plausible narrative?" he said.
The trial, before Justice Raynor Asher and a jury of seven women and four men, is scheduled to last four weeks.
