Season six of the multi-award winning podcast Expanse: The Nannup Four explores the dark secrets, hard questions and lost chances around one of Australia's most baffling missing persons cases.

In 2007 four people disappeared from an isolated blue farmhouse on the outskirts of the Western Australian town of Nannup. They left behind the scatterings of a life, a letter on the door and bizarre rumours. What emerges is a story of control, hidden identities and a dark online cult as everyone is left asking, what could I have done differently?

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