Billie Walker Mystery Books in Order

The Billie Walker Mystery series drops readers into Sydney just after the Second World War, when uniforms are being packed away but the damage of the conflict is still fresh. The mood is smoky and glamorous on the surface, but grief and secrets sit underneath almost every conversation.

Billie Walker is a former war reporter who has come home without her husband, Jack, a fellow journalist missing in Europe and presumed dead. Rather than return quietly to society life, she reopens her late father's inquiry agency, determined to earn her living on her own terms and to keep chasing stories that matter.

As an inquiry agent in 1946 and 1947 she treads a line between accepted and scandalous work. Much of her early business involves following cheating husbands for women who need proof in divorce cases, but bigger jobs soon arrive: a missing immigrant boy, a wealthy client's vanished spouse, hints of war criminals hiding in plain sight. At her side is Sam Baker, a young veteran who serves as her assistant, lookout and moral compass.

Across the books you see postwar Sydney from many angles. There are fashionable nightclubs, auction houses and dance halls where ration coupons and black-market money quietly change hands. There are back-lane boarding houses, dusty country towns and the offices of people who would rather Billie stop asking questions. Her baroness mother, a sharp-tongued survivor of European aristocracy, and contacts such as Shyla, a resourceful Aboriginal informant, remind you that class, gender and race all shape who gets listened to.

The investigations do not stay in Australia. One case pulls Billie to London and Paris, cities still full of bomb damage and people searching for loved ones who never returned from the war. Another leads from Sydney's harbour to the Italian coast, piecing together an old family connection that threads through a 1907 voyage, a 1943 air raid and the uneasy calm of 1948 travel on a luxury liner.

Although there is plenty of action, the series is as interested in the quieter costs of war as it is in gunfights and chases. Billie meets refugees, queer survivors, damaged soldiers and women who stepped into new roles during the conflict only to be pushed aside afterward. Her cases often circle questions of stolen lives and stolen art, and what justice looks like when official channels are stacked against the vulnerable.

Expect a blend of noir atmosphere, fashion details and grounded historical crime, with a heroine who uses lipstick and charm as tools but never lets them be mistaken for weakness. The novels follow an ongoing arc involving Billie's missing husband and her father's past, so they are best read in order, starting with The War Widow/ Dead Man Switch, then The Ghosts of Paris and The Italian Secret.