The spark of life, fount of emotion, house of the soul - the heart lies at the centre of every facet of our existence. It's so bound up in our deepest feelings that it can even suffer such distress from emotional trauma as to physically change shape. Practising cardiologist Sandeep Jauhar beautifully weaves his own experiences with the defining discoveries of the past to tell the story of our most vital organ. We see Daniel Hale Williams perform the first open-heart surgery and Wilson Greatbatch invent the pacemaker - by accident. Amid gripping scenes from the operating theatre, Jauhar tells the moving tale of his family's own history of heart problems and, looking to the future, he outlines why the way we choose to live will be more important than any device we invent....