By Kirsty Johnston: The murder of Harvey and Jeannette Crewe in their Pukekawa farmhouse in 1970 remains New Zealand's most infamous cold case.

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Len Demler told the reporters what he had told the police: he had found the house empty except for baby Rochelle in her cot. "There were dinner dishes on the table," he said. "There was blood on the carpet and on the chair. But the house was not in disorder. The car was in the garage. The three dogs were in their kennels. They couldn't have been fed, but it was a mystery that they had survived for five days."

This week, 'The Crewe Murders: Inside New Zealand's most infamous cold case', a new book from Massey University Press written by Kirsty Johnston and James Hollings.

Award-winning investigative journalist Kirsty Johnston joins the podcast to discuss the case and read an excerpt of the book herself.

The murder of Harvey and Jeannette Crewe in their Pukekawa farmhouse in 1970 remains New Zealand's most infamous cold case. It spawned two trials, two appeals, several books, a film, and eventually a royal commission finding of police corruption - and, the only free pardon granted by the New Zealand giovernment in history.

And the case is still unsolved.

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