Michael Mosley tests the extraordinary claim that we might only need a few hours of sleep - if that - each night. Having given up a medical profession because of his inability to function without sleep and, like the rest of us, anxious to squeeze more out of each day, Michael wants to see if there really is a cure for sleep. He attempts to forego sleep for as long as possible, with the help of the world record-breaker for staying awake. He also meets a professor depriving human guinea pigs of sleep, and a scientist keeping flies awake for much longer, to discover if we need sleep at all. He visits Texas to speak with contenders in an annual sleep deprivation contest, and hears how it ended in tragedy. Eventually he turns to prescription drugs, only to discover that they do not hold the cure for sleep that he had hoped for.

In a funny and thought-provoking film that moves from the quirky to cutting edge science, Michael Mosley wants to find out if he can live forever. He embarks on a calorie restricted diet, injects himself with testosterone and visits a life-extension house, all with the aim of seeing if any modern elixirs of youth actually work. While he monitors his response to these techniques, he visits some remarkable individuals whose lives are intrinsically defined by the science of aging: the brave girl suffering from an accelerated ageing disease, the 62-year old woman who claims she looks forty thanks to daily hormone injections; and the scientist who has pioneered the creation of tailor made replacement organs using stem cells. What he learns about extending the human lifespan leads him to wonder, would he want to?

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