On the 100th anniversary of the devastating pandemic of 1918, Jeremy Brown, a veteran ER doctor, explores the troubling, terrifying, and complex history of the flu virus, from the origins of the Great Flu that killed millions, to vexing questions such as: are we prepared for the next epidemic, should you get a flu shot, and how close are we to finding a cure. Influenza is an enlightening and unnerving look at a shapeshifting deadly virus.