We Who Decide is a story of deceit, lies, and ambiguity; a fictionalised tale of a woman who became a doyen of post-war Sydney's haute couture. It describes the life of Shoshanna Liebler, an 18-year-old European Jewess who, on the eve of the Anschluss of 1938, flees Austria, for Australia. A renowned high-fashion designer, known affectionately as ZaSu, collaborates with her parents and brother in the family business. For more than a century, the House of Liebler designed and manufactured military and police uniforms for the old Austro-Hungarian Empire. Determined to modernise the group's business, ZaSu develops a portfolio of affordable creations for Europe's leading fashion houses.

Entrepreneur Ashton Frost, of the fictional Sydney-based Frost Emporium, is determined to incorporate the Liebler style into his family's retail chain. Frost finances ZaSu's journey to Australia, but her new life begins in a detention wing of the Long Bay prison. Upon release ZaSu decides to obscure her identity, religion, and sexuality if she is to succeed in a conservative country about which she knows nothing. Cut off from her family and a trusted aide-de-camp, ZaSu is desperate to uncover the truth about the fate of her mother, father, and brother.