In the township of Khancoban, beneath the celebrated Snowy Mountains Scheme, journalist Ellie Kaplan inherits a cottage from a great-uncle she never knew existed. When her father urges her to sell it sight unseen, her journalistic instincts are triggered.

What begins as curiosity about a mysterious relative evolves into a dangerous investigation as Ellie discovers Nikolai Popov spent decades documenting a deadly secret—the deliberate exposure of migrant workers to uranium deposits during the Scheme's construction, followed by a sophisticated cover-up spanning generations.

As Ellie uncovers journals, photographs, and scientific samples hidden throughout the cottage, she realises her great-uncle was continuing work begun by another relative, Lena Popova, a geological engineer who disappeared in 1960 after raising concerns about worker safety and environmental contamination.

With the 75th anniversary celebrations approaching, powerful interests are implementing plans to permanently seal access to contaminated tunnels, destroy remaining evidence, and silence anyone asking inconvenient questions—including Ellie.

The town's apparent tranquillity masks decades of surveillance, suppression, and environmental crime. Each revelation brings Ellie closer to understanding her own family's connection to a buried history of corporate greed, Cold War uranium extraction, and calculated endangerment of a multicultural workforce.

In a community where some truths have remained submerged for seventy-five years, Ellie must expose the contamination before the evidence—and she—are permanently entombed beneath Australia's greatest engineering achievement.