The last episode explores happiness. It is critical to well-being, yet it remains such an elusive goal for many. What is it, why is it important and how can we attain more of it? Viewers meet individuals facing major turning points in their lives - a job loss, a cancer diagnosis, the death of a child, an accident - as well as those facing more common struggles.

The first episode looks at the importance of relationships and why they are central to our emotional well-being. What are the cognitive and neurological processes underpinning our everyday interactions, and can they help us to understand why some relationships flourish and others fail?

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.