Chilling new footage shows the final moment a pregnant mum-of-two returned from a business trip unaware her husband was waiting indoors to kill her.
Shanann Watts, 34, was captured by the doorbell camera at her home after arriving home from the airport and exiting her friend’s car to get into the house in the early hours of August 13, 2018, reports The Sun.
In what is believed to be the last time she is seen alive, the video shows her friend waiting until the 15-weeks-pregnant mum is inside the property before driving away.
Within hours, Shanann, unborn baby Niko, and her two daughters had been slaughtered by her husband Chris Watts, 33.
The disturbing footage has only just been released, and at the time Shannan is seen entering the home it is unclear if her two daughters were alive or had already been killed.
Watts slaughtered Shanann and their two daughters Bella, four, and Celeste, three, at the family home in Fredrick, Colorado after their marriage began to fall apart amid financial problems and his infidelity.
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The girls’ bodies were found three days later in an oil well on the property of Watts’ employer, Anadarko Petroleum, his lawyers said.
They had been in the well so long that skin came off the daughters’ bodies as they were removed from the seven-metre tall tanks.
Shanann and her unborn baby boy were found in a shallow grave 100 metres away.
It is believed Shanann was strangled and the two girls were suffocated.
Watts confessed to the murders after being shown CCTV footage from a nearby property that wrecked his alibi.
He had claimed that Shanann and the girls had gone away for the day, but the neighbour’s surveillance only caught Watts leaving the house on the day in question.
In video published on the Daily Mail, he is seen watching the footage for the first time before throwing his hands up in disbelief and realising he has been caught.
The murders happened at a time when the family was mired in crippling debt and Watts was having an affair.
Watts bought the home in May 2013, but the pair filed for bankruptcy in June 2015, when their home was still valued at $US400,000 ($A558,000), CNN reports.
They were in about $US70,000 ($A97,000) of debt from credit cards and student loans, and the couple had less than $US10 ($A14) in their joint savings account, according to bank records.
Prosecutors said Watts was having an affair with a work colleague and Shanann was desperately trying to save their crumbling marriage.
Watts pleaded guilty to first-degree murder in November and to other charges in the deaths of his wife and daughters.
He was given five life sentences without the possibility of parole.
Watts is serving his sentence at the Dodge Correctional Institution in Wapun, Wisconsin.
He was moved there on December 3 in an inmate exchange for his own safety.
— with The Sun