* How many minutes can you now survive after cardiac arrest? * What do new medical techniques teach us about consciousness? * How will these change our views of who we are? In 2012, two football stars collapsed while playing. Both were technically dead yet, while Fabrice Muamba received hypothermia treatment and recovered, his counterpart in another country did not. In The Lazarus Effect, Dr Sam Parnia, a critical care physician and one of the world's leading experts on the scientific study of death, uses fascinating stories, as well as the very latest research, to investigate what happens during cardiac arrest. He also explains how medical advances are revolutionising our chances of survival. Parnia shows how these developments have introduced a controversial `grey zone' between heart failure and irreversible death, where death is not a single point but a process. What does that mean for our definition of death? And how can we account for the way the human mind continues to exist after death has begun? These questions come from the heart of a debate that has profound ethical, scientific and philosophical implications for us all, not least the fact that, soon, we will have more power over life and death than ever before.