A medical mystery, THE ILLNESS & THE ODYSSEY tracks the pursuit of a possible clue to a cure for Alzheimer's, Parkinson's and other neurological wasting diseases which may be related to a mysterious neurological disease found only among the native people on the remote island of Guam. Lytico-Bodig is a debilitating disease suffered by Guam's Chamorro population. It manifests as a brutal combination of Parkinson's disease, Alzheimer's disease and ALS (Amyotrophic Lateral Sclerosis). Because it is found only in an isolated location -- giving medical researchers a narrow set of variables to study and understand -- it is believed that the information learned about Lytico-Bodig could lead to the discovery of a cure for other neurodegenerative diseases that attack the brain. Featuring commentary by noted author and neurologist Dr. Oliver Sachs, THE ILLNESS & THE ODYSSEY follows the work of three scientists, each of whom has dedicated the major portion of their careers to providing an explanation about this medical mystery "whodunit." As the decades-long drama unfolds, the debate among the scientists is intense and passionate, to the point of hostility. With their careers at stake, each tries to discredit the other and claim the legacy of finding the clue that unlocks a cure to these tragic diseases. Based on Dr. Sacks' book The Island of the Colorblind, the film traces the struggle to solve a medical mystery plaguing a native population in Guam.