How long can mental illness stay hidden, especially from the eyes of trained experts? This program rejoins a group of ten adults—five of them healthy and five of them with histories of mental illness—as psychiatric specialists try to spot and correctly diagnose the latter. Administering a series of collaborative and one-on-one tests, including assessments of personality type, physical self-image, and rational thinking, the panel gradually makes decisions about who suffers from depression, bipolar disorder, bulimia, and social anxiety. At the conclusion of the program, the professionals confess to a wariness of their own diagnosis methods, and labels of “sick” and “normal” are seen in a new light. A BBC/Science Channel Co-production. Part 2 of the series How Mad Are You? A Search for Insanity. (51 minutes)