15-year-old Canterbury teenager, Kirsty Bentley from Ashburton went missing after taking her dog for a walk on New Year's Eve in 1998 - her body was found just over two weeks later. Stuff journalists Blair Ensor and Martin van Beynen recently completed an investigative piece on the unsolved case.

It's one of the most high-profile cold cases in New Zealand's history - the murder of Canterbury teenager, Kirsty Bentley.

The 15-year-old from Ashburton went missing after taking her dog for a walk on New Year's Eve in 1998, and her body was found in bushes near the Rakaia Gorge just over two weeks later.

The case has never been solved.

Eighteen years after her body was discovered, the coroner ruled the death of Kirsty Bentley was not accidental.

Her older brother, John, the last person to see her alive, told police she left the house late in the afternoon to take the family dog for a walk.

Two weeks later, on the day before her 16th birthday, Kirsty's partially buried body was found 60km away near the Rakaia Gorge.

Stuff journalist, Blair Ensor and Martin van Beynen wrote an indepth investigative piece on the case.

Go to this episode on rnz.co.nz for more details