The haunting murder case that's now a gripping new podcast.

In June 1994, David Bain’s entire family was killed while he was out on his morning paper route.

Fifteen years later he was acquitted for their murders.

Now a new podcast, Black Hands: A Family Mass Murder, is delving into the shocking crime that’s split public opinion in New Zealand for the past 23 years.

While many believe Bain was responsible for the crime, others steadfastly stood by him until he was granted a retrial in 2009.

The podcast starts in the immediate aftermath of the mass murder, when Bain apparently re-enters the Dunedin home after completing his morning paper route.

The then 22-year-old finds his mother Margaret, his father Robin, and siblings Arawa, Laniet and Stephen, all dead in the family home.

He calls emergency services and when police at arrive at the home, they find David unconscious in an upstairs bedroom. However, the medics on site believe he's faking it.

Soon after the police realise there could only be two possible suspects for the murders - Robin, the family's patriarch who was dead on the floor, David, the only remaining living family member.

David was eventually charged with all five murders and in 1995 he was convicted and sentenced to mandatory life in prison with a minimum non-parole period of 16 years.

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However, his case attracted the interest of businessman and former All Black Joe Karam who, with the help of Bain's legal team, successfully appealed to the Privy Council, which ruled there had been a 'substantial miscarriage of justice'.

Bain was granted a retrial and in June 2009 he was acquitted of all the charges.

Speculation over the case has continued, however, as the police still don't have any definitive answers.

The podcast dives into the Bain family, their unusual history and family set up, and how a range of different factors could have culminated, creating a perfect storm for mass murder.

All 10 episodes of Black Hands: A Family Mass Murder are available on iTunes now.