A desperate young man arrives at the office of a renowned investigator with an impossible request: prove the innocence of the woman he loves, who stands accused of murdering her own father and stepmother. The victims were found dead in their elegant country mansion under circumstances that baffle even the most experienced physicians-no marks of violence, no trace of poison, yet both unmistakably murdered.

As the investigation unfolds, dark family tensions emerge from behind the façade of wealth and respectability. A torn shirtwaist discovered in a brook, mysterious footprints near the water's edge, and a stepbrother searching frantically through the dead woman's belongings all point to secrets that someone will kill to protect. With the coroner building his case and public opinion turning against the accused, time is running out to uncover the truth hidden within the mansion's walls.