2. Second Opinions

The parents of bright and charming, Sadie, 7, seek alternatives to the devastating brain procedure doctors propose to treat her frequent seizures.

3. The Wisdom of the Crowd

Day by day, Willie, 46, loses pieces of himself. He has memory loss, seizures, mood sings, a brain lesion -- but no diagnosis. Can the crowd help?

4. Looking for a Village

Six-year-old Kamiyah suddenly and briefly go limp dozens -- sometimes hundreds -- of times a day. Now the search is on to find others like her.

5. A Question of Trust

Lashay, 17, can't hold anything down that she eats or drinks. But negative interactions with previous doctors leave her family leery of the crowd's advice.

6. Déjà Vu

Matt, 20, experiences fainting spells that stop his heart, each one preceded by a sense of déjà vu. But is the issue with his heart -- or his head?

7. Paralyzed

Two very different people are desperate for a diagnosis to their unexplained paralysis: textbook "good patient" Joe, 61, and more skeptical Ann, 44.