Margaret Kirstenfeldt was a much-loved, young mum with plenty of friends, who suffered a violent, bloody death in the tiny Queensland town of Sarina.

But was it suicide or murder?

Expert opinions have swung wildly for 40 years. Could a killer still be on the run?

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More from Pendulum:

• Mum Margaret Kirstenfeldt feared for safety, hid knife under bed
• Person of interest was identified before mum’s death was ruled a suicide
• Fresh eyes offer same conclusion in Queensland mum’s death