Dr Bente Apstein disappears from her home in New Farm, Brisbane. Her husband, Samuel, a mining engineer, is accused of murder, but the Police fail to find any incriminating evidence. Distraught by Bente's disappearance, Samuel is about to leap from a cliff when he is saved by the fortuitous arrival of Dr Mark Altree, an old university friend. Altree and his wife, Sonia and their associate Dan Hawkes resolve to determine what happened to Bente.