Hannie Rayson once again affirms her place as one of Australia's finest playwrights in Nadia Tass' tightly directed, thought-provoking and absorbing production of Extinction. Rayson writes with integrity, intelligence and profound insight into the debates that determine our attitudes towards the environment, coal mining, the preservation of endangered species, the precarious sphere of human relationships and the abiding preoccupation with our mortality.

At the close of the drama the questions continue to resonate. In a brilliantly balanced display of moral and ethical conundrums, Rayson elicits complete engagement with her ideas and the lives of her characters. Tass and her superbly talented actors of Red Stitch Actors Theatre avoid any vestige of didactic postulating. This is a deeply human drama, probing the mind and touching the heart and exploring the essence of our fleeting mortality. In Extinction, Rayson is more than a prophetic voice for our time. She is also a consummate storyteller, with a plot laden with drama, complicated by conflict, and laced with humour and surprise.

Mining executive Harry Jewell (Colin Lane) has run over an endangered tiger quoll during a stormy night in the Otways. He takes it to the nearest veterinary clinic where research assistant Piper (Ngaire Dawn Fair) attempts to heal it before the vet Andy (Brett Cousins) arrives. Jewell seeks to support a plan to preserve the quoll by offering money to Andy's sister, Heather (Natasha Herbert) who is head of a university research department, and Piper's supervisor.

The moral dilemma in the face of economic pragmatism is immediately apparent. This is complicated further by the seeming frailty of human emotion and sexuality and Andy's distressing confrontation with his own mortality. Rayson's tangled web of deceit exposes our obligation to consider and act upon the issues that concern us whether it be the regard for our wildlife, the proper use and preservation of the environment, the responsibility to create clean energy and the honesty and integrity of the human condition.

The questions that linger at the end of the play contain the answers implicit within Rayson's drama. In a production as entertaining, stimulating and significant as Extinction, an audience may draw their own conclusions, but the final full screen image of the tiger quoll reminds us that we have a duty to preserve this species as well as our own through responsible management of the environment. And the human heart and mind? Is that also under threat of extinction?

Extinction echoes the theatre of the great Norwegian dramatist Henrik Ibsen who postulates social change through the actions of the individual. This is reason enough, as well as the outstanding production and performances by every member of the cast and production team, to regard Extinction as a must-see example of first-rate Australian theatre.