She has investigated some of the country's most high profile crimes, been at the frontline of policing for almost three decades and is now at the helm of one of the busiest districts in the country.
Superintendent Karyn Malthus has taken over as the District Commander for the Auckland City police district, which covers the CBD and fringe suburbs stretching out to St Heliers, Onehunga, Avondale and Waiheke and Great Barrier Islands.
Geographically the smallest district, it has the biggest population and one of the most diverse, with about 420,000.
Malthus oversees about 1000 police staff and says her vision for the district is simple.
"We want to work with these communities around ensuring that they are safe, and that they feel safe," she said.
Malthus was appointed District Commander in September 2016, taking the reigns from Richard Chambers who was promoted to the role of Assistant Commissioner, Investigations and is now based at Police National Headquarters.
Born in Gore, Malthus' family moved north and she attended Rotorua Girls High and joined the police in 1987.
She moved through the ranks of the criminal investigation branch and after 13 years moved to Counties Manukau where she spent just under a decade investigating some of the country's most horrendous crimes.
"There is no one case that is more significant than others," she said.
"One of the tragedies is we get to meet tremendously wonderful people in circumstances that, otherwise, we would never meet."
Karyn Malthus, new Auckland Police District Commander. 14 December 2016. New Zealand Herald photo by Jason Oxenham.
Most recently Malthus oversaw the review into the way police handled the Roast Busters investigation.
The scandal centered around West Auckland teens Beraiah Hales and friend Joseph Parker who were allegedly the ringleaders of a group called the Roast Busters.
The pair and several other members have been under watch by police since late 2011 when a 13-year-old made a formal complaint about the youths sexually assaulting her.
No one was charged after two exhaustive police investigations.
Earlier in her career in the CIB Malthus headed the manhunt for Ese Junior Faleali'i who shot dead two men - a pizza worker and a week later a bank worker - during a P-fuelled robberies in Auckland.
You broke into her Manurewa home looking for cash and punched Ping in the head, stomped on her chest and dragged her by the hair as he tried to stuff her into a wardrobe.
The 80-year-old died in hospital three days later.
"These cases are all challenging," Malthus said.
"There's not one that is the most significant, they were all significant."
Before taking on her current role Malthus did stints in Northland and Auckland as the district crime manager and Tasman as the District Commander.
So what is her vision for her new patch?
We have a strategy and vision for police in New Zealand and for this district it's really no different - safe communities and a sense of trust and confidence in the police.
"In Auckland City we have a lot of issues around alcohol-fuelled violence, not just down town. So it's about what we can do to work with the community and council to ensure that safety and feeling of safety."
Malthus said family harm was also a priority.
"It is a significant issue and we invest a great deal of time nationally and locally into that," she said.
"Organised crime is another one, understanding what the drivers are.
"This police district has a really good model, a really good structure and there are some tremendously talented people working for us.
"My job is to enable them, to make sure they've got what they need to do their jobs - I'm not here to reinvent the wheel, it's about enabling and making sure my people have what they need and striving for better outcomes."
After 29 years in the police Malthus is just as passionate about the job as she was when she graduated from Police College.
"It's about the people," she said.
"I really enjoy what this role gives me, the opportunity to get out there and see what my people are doing and to try and identify what can be improved.
"It's about 'what can I do to make this easier for you?' I'm here to do good, to effect some change.
"Our people are passionate and I just loved hearing about what they are doing and how they are engaging. It keeps me inspired."
Malthus is the first woman to head the Auckland District, and incidentally her appointment came in the 75th anniversary year of women in policing.
However she said gender had nothing to do with her career progression.
"Police is a merit-based organisation," she said.
"Yes, I am the first woman to be the District Commander of Auckland City, and I know that is significant for women in policing, but for me and my career, this was just a natural progression as opposed to it being about that."
New face in Waitemata District's top seat - meet Superintendent Tusha Penny
New Waitemata District Commander Superintendent Tusha Penny. New Zealand Herald photograph by Mark Mitchell.
Superintendent Karyn Malthus isn't the only new top cop on the block.
The Waitemata District has welcomed Superintendent Tusha Penny, also the area's first female commander.
Penny graduated from Police College in 1992 and has worked her way from the front line and general duties to the CIB.
Over her 25 years as an officer she worked Gisborne, Auckland and most recently Wellington, where she was appointed the organisation's first national manager of child protection and sexual violence in 2015 before taking on the role of national prevention manager.
The Herald recently spent time with Penny while she was in that role, speaking to her for the family harm-focused campaign We're Better Than This.
Penny was welcomed to the Waitemata District at a powhiri at Hoani Waititi Marae in December.
She takes over from Superintendent Bill Searle, who was promoted to the role of Assistant Commissioner: Prevention based in Wellington at Police National Headquarters.
