Jeanne Nollman fails to hit puberty and is being told that she is just a late bloomer. Her doctor tells her that her ovaries are underdeveloped and can become cancerous. But actually, it is revealed that he has been hiding the fact that her gonads haven't developed at all into ovaries. After more tests, Jeanne finds out she has a rare genetic disorder called Swyer syndrome, which gives her XY chromosomes, but renders her body unable to produce hormones essential for puberty. Plus, Mary Brown is a healthy, active mother of two, when suddenly, she develops a collapsed lung. She suffers shortness of breath, spotted vision, pain in her shoulders, and sensations of bubbles going down her back and is diagnosed with a rare lung disease called lymphangioleiomyomatosis (LAM). Every year, millions of Americans fall prey to real-life medical mysteries ailments that go undiagnosed or misdiagnosed for years. Their lives are thrown into turmoil as medical professionals struggle to understand their baffling conditions. Mystery diagnosis tells their stories. Through interviews and dramatic recreations, each medical mystery is recounted in vivid detail. Symptoms emerge, specialists are called in, but still the daily struggle continues. And then one day, because of a patients relentless pursuit of an accurate diagnosis, or a forward thinking doctor, the problem is solved and a true diagnosis given.