Frankie Paige, a young, carefree hairdresser in Pittsburgh, begins experiencing bizarre and painful wounds resembling the crucifixion of Jesus Christ, known as stigmata. The phenomena attract the attention of the Vatican after Father Andrew Kiernan, an investigator of miracles and debunking frauds, is sent to verify her claims. Skeptical at first, Father Kiernan witnesses the inexplicable nature of Frankie's wounds and is drawn into the mystery. As he delves deeper, he finds himself conflicted between scientific rationale and spiritual implications. The occurrences become more frequent and violent, putting Frankie's life at risk and raising questions about the origins and intentions behind her suffering.

Father Kiernan's exploration leads him to uncover sinister forces within the Church that have a vested interest in the events surrounding Frankie. While struggling to protect her from physical harm, he also finds himself grappling with a potential theological upheaval, as the messages imparted through her suggest revelations that threaten established religious doctrines. The story navigates a complex web of faith, corruption, and truth, leaving audiences questioning the nature of belief and the authenticity of spiritual experiences.