A routine abdominal scan on a 75-year-old woman uncovers something her doctors initially refuse to believe: a fetus that has been lodged in her body for 46 years. The film traces the medical investigation into her case, a rare condition known as a lithopedion, or "stone baby," in which a fetus dies outside the uterus, usually during an ectopic pregnancy, and calcifies rather than being reabsorbed or delivered. Doctors and specialists explain how such a pregnancy can go unnoticed for decades, walking through the scans and surgical findings that confirmed the diagnosis. Interviews with the medical team lay out why the condition is so rarely seen and what the calcified mass reveals about the pregnancy that produced it. The film treats the case as a genuine medical mystery, following the reasoning doctors used to work out what they were looking at and why a woman could carry the remains of a pregnancy for nearly half a century without knowing.