Could she, a professor of mathematics, follow the simple arithmetic of suicide, or would her courage fail her?A calculated terrorist attack on Australian soil raises alarm for the local police. Greater horrors lie behind the catastrophe of an imminent second action. The history of the early twenty-first century rests with three main characters: Josh, an ex-navy clearance diver; Jack, his Sydney Water Police Officer partner; and Inaya, a woman with a past.

In making their judgements to balance duty and faith, they are each faced with man's most basic instinct: the will to survive. They cast their lots. Decisions are made that draw all three to a climax that will change them forever.