Celebrating her 45th birthday at her neighborhood pub, podcaster Alix Summer unexpectedly encounters a seemingly ordinary woman named Josie Fair, who is also marking her 45th milestone.
Their paths cross again a few days later outside Alix's children's school, where Josie hints at being an intriguing subject for Alix's podcast, claiming to be on the brink of significant life changes.
Intrigued, Alix agrees to conduct a trial interview, only to uncover that Josie's life is far more complex and mysterious than initially presumed. Despite feeling unsettled by Josie, Alix finds herself drawn to unraveling her secrets.
As Alix delves deeper, she gradually realizes that Josie is harboring dark and undisclosed truths. Before she knows it, Josie manages to insinuate herself into Alix's life and home.
As suspicions mount, Alix becomes increasingly perplexed about the true identity and intentions of Josie Fair. What secrets is Josie hiding, and what has she done?