AN unspoken apology owed for a criminal act and its consequences lies at the heart of Gail Jones's stunning new novel. "The freight of unsaid grievances and encumbering sorrows" haunts her narrative.

Memory was a central theme in Jones's previous novel, Dreams of Speaking; here, she explores how forgetting shapes and shadows our histories. While its ethical and political themes resonate, this is an emotionally-engaging novel that revels in the specificities of its imagined world.

An English anthropologist, Nicholas Keene, drags his unstable wife Stella to the outback of north-west Australia, his head full of universalising myths and dreams of academic acclaim.

Their daughter, Perdita, is raised in bookish and Spartan isolation, neglected by her parents. Her life is transformed when Mary, an Aboriginal girl, comes to look after Perdita in their tumbledown shack "taut with conjugal unhappiness". The two girls forge a lifelong friendship, with tragic consequences for both.

Jones subverts the murder mystery, with its expectations of a narrative driven by the enigma of culpability towards the comfort of resolution. Here the central crime is elusively revealed through "blind-spotted" memory, repressions and revelations.

Restitution is not made; no tidy conclusions are drawn. Jones distinguishes between the many kinds of silence and language that claim us, rather than simply judging guilt and innocence.

Silence is not only the withheld "sorry" of reparation; it is also the cold family climate of repression.

Conversely, it is the companionable sisterhood of reading that the girls establish. In their silence it is possible "to listen, in intimate and sweet propinquity, to air entering and leaving a resting body". Jones chooses to speak of silence, not of the silenced. She is careful not to ventriloquise Aboriginal histories. The elegiac and occluded nature of her narrative is an ethical as much as an aesthetic choice.

Many different languages are woven through the novel, from Aboriginal songs "drifting and braiding and dissolving into the darkness" to Stella's obsessive recitations of Shakespeare.

Shakespeare saves Perdita from her loneliness, as surely as he condemns Stella to the asylum.

Jones writes beautifully about small lives and their rippling connections to larger stories. Perdita regrets that she never said "sorry" . . . the ghost of that unarticulated apology reverberates across the continent to the present day.