Everyone knows someone who suffers from manic depression. But it's a disease that's little talked about and little understood. This two-part documentary series, presented by Stephen Fry, sets out to explore the highs and the lows, and the causes and the treatments of a condition that may affect as many as 2% of the population.Motivated by his own personal battle, Stephen Fry goes on an emotional but entertaining journey - an A to Z of manic depression - where he chats to stars in Hollywood and Britain such as Carrie Fisher, Richard Dreyfuss and Rick Stein, as well as ordinary people who juggle this illness with their working lives; and he visits the surgeries of psychiatrists and the labs of researchers who are trying to help control the condition.