Summary The second episode looks at emotions that are commonly regarded as obstacles to happiness - anger, fear, anxiety and despair. Why do we have these emotions and how can we best manage them? Everyone wants to be happy, but nature has a different plan. Our brains are designed for survival, and the negative emotions they create are vital to that mission. But those negative emotions can spiral out of control with debilitating effects. Viewers meet a woman whose inability to control her temper is jeopardizing her relationships, a college student whose fear of flying is limiting her life and a teenager who is struggling to overcome clinical depression on the eve of attending college. Viewers also meet veterans with post-traumatic stress disorder (PTSD) and follow their journeys to find effective treatment. Across the episode, science reveals that we are two minds - a rational brain that's relatively new and an emotional brain that's older than time. Sometimes emotion overwhelms reason, sometimes reason outwits emotion; it is the endless struggle that makes our lives so painful, so joyous and so interesting.

• Documentary