Is depression a persistent low mood, or is it a range of symptoms? Can it be expressed through a single diagnosis, or does depression actually refer to a diversity of mental disorders? And will there ever be a cure? In seeking the answers, Alex Riley finds a rich history of ideas and treatments—and takes a gripping narrative journey, packed with fascinating stories like the junior doctor who discovered that some of the first antidepressants had a deadly reaction with cheese.

"Interweaving memoir, case histories, and accounts of new therapies, Riley anatomizes what is still a fairly young science, and a troubled one."—The New Yorker