Dr. Abe Tessman is conducting a PET scan study of the brains of stroke victims, with little success. One day, he discovers that his technology could be put to better use researching Alzheimer's patients. A new study is launched, with increasing success. But all is not well. Abe is plagued with memories of his painful divorce, which was caused by his mother's struggle with Alzheimer's. At first just brief flashes of daydreaming, it becomes clear that he has Alzheimer's himself. Using the PET scanner, Abe watches his brain deteriorate over time. He tries to cover up his condition so that he can continue his research, but he can't forget the past.