Herald senior journalist Anna Leask covered this case from the outset, reporting on the trial and revealing the dark history of Mitchell.
It emerged after he was convicted of the Riverhead attack, that he was also responsible for an unsolved 1992 rape.
Evidence found in the 2017 investigation linked him by DNA to a similar attack on a woman walking home from central Auckland at night.
Leask also spoke to a woman raped by Mitchell in 1984 when she was just 19 and dabbling in sex work for the first time.
And she tells the story of the first woman Mitchell was jailed for attacking - a week after he turned 15 in 1974.
Mitchell was jailed indefinitely in 2019 for the brutal Riverhead attack and the 1992 rape.
Justice Sally Fitzgerald said Mitchell was highly likely to reoffend against vulnerable females in future and sentenced him to preventive detention.
She said he had expressed no empathy at all for his violent attacks.
Further, he still denied his brutal attacks on unsuspecting and innocent strangers - and had yet to accept he had a problem for preying on vulnerable women.
The sentence means Mitchell will stay in prison until the Parole Board deems that he is no longer a risk to the community - to women.
And, even if he is ever released on parole, he must remain under the management and monitoring of Corrections for the rest of his life.
Mitchell was sentenced on his 60th birthday and the court heard that due to serious health problems including diabetes and cancer, he will likely die behind bars.
This episode of A Moment In Crime contains material including references to sexual assault and violence and might be distressing for some listeners. If you or someone you know needs help, please refer to the bottom of this story for a list of services and agencies.
A Moment In Crime is written, hosted and produced by Leask with help from the NZME Sound, Vision and Creative team.
Leask has been covering crime and justice for the Herald for more than a decade and has reported on most of the major incidents and events over that time.
"Each month I'll take you inside some of our most infamous incidents, notorious offenders and behind the scenes of high-profile trials and events to show you what's really happening in your backyard," she said.
"Heroes and villains battle for justice to be done, and it seems no matter how horrifying the story, we always want to know more.
"If you want to know more about the cases that have shocked and shaped our nation - from murders and massacres to violent villains and the utterly unbelievable - join me for A Moment In Crime."
In our first episode, we looked back at the Christchurch terror attack - what unfolded on March 15 and how it changed New Zealand.
The podcast has also delved the cold case murder of Kayo Matsuzawa, the murder of Feilding farmer Scott Guy, the cold case of schoolgirl Alicia O'Reilly, double killer Jason Somerville - infamous for the Christchurch House of Horrors, and the Lundy and Crewe family murders.
More recently Leask has revisited the murders of the Kahui twins and given an unique insight into the offending and harm caused at the Gloriavale Christian community on New Zealand's West Coast.
If you have a crime or case you'd like us to consider covering, email anna.leask@nzme.co.nz
NZME has a raft of other podcasts produced by journalists and broadcasters from the Herald, Newstalk ZB, ZM, The Hits and others - all available on iHeart radio.
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SEXUAL HARM - DO YOU NEED HELP?
If it's an emergency and you feel that you or someone else is at risk, call 111.