This post deals with graphic descriptions of domestic violence and may be triggering for some readers.
Chris Watts is currently serving three consecutive life sentences for the murder of his 34-year-old pregnant wife Shanann, and their daughters Bella, four, and Celeste, three, in Colorado in August 2018.
And this week, new details have emerged about just how deceptive Watts was to all the people in his life after murdering his family.
Although Watts originally fronted news cameras with a desperate appeal for help when his wife and two young daughters were reported missing, the truth soon emerged when the bodies of Shanann, Bella and Celeste were recovered from an oil field owned by the petroleum company that Watts worked for.
His wife and his unborn son had been buried in a shallow grave, and his daughters submerged in crude oil vats.
Watch: What Chris Watts' latest confession reveals. Post continues below.
After Watts' shockingly calm initial plea on TV for his wife and children, he was brought in for an interview with investigators.
FBI agent Graham Coder tried to get an official statement out of Watts, but he wasn't responding emotionally to the "very, very tough questions," says CBI agent Tammy Lee, who also helped get a confession out of Watts.
Eventually, Watts slipped up and began talking about his wife and daughters in the past tense, prompting warning bells to go off in the investigators’ minds.
"If he is hoping and believing that they're still alive, why would you start talking about them in past tense?" mused Lee on Oxygen’s Criminal Confessions programme.
The next day, under pressure from a lie detector test, Watts admitted to having an affair, something he had previously denied. Investigators changed their line of questioning after this as they were worried Watts would "completely… shut down". They also claimed they already knew about the affair, insinuating that they had more information than they really did - presumably, to make Watts panic.