The final episode of the series ponders the fate of planet Earth. Neil deGrasse Tyson opens with a reflection on science and those who help us understand it: 'We all feel the weight of the shadows on our future, but in another time, every bit as ominous as our own, there were those who could see a way through the darkness to find a star to steer by.'
The young Carl Sagan and Neil Tyson first discovered their passion for science at the NY World's Fairs of the past. We visit the dazzling Pavilions of the 2039 NY World's Fair, where problems we currently think intractable have been plausibly solved through public commitment and scientific imagination. And our baby is a woman now, with a baby of her own and a future bright with possibilities.

Half of the population in Western society suffers from being overweight. Cardio-vascular diseases, diabetes and cancer are epidemic. Our meat consumption has quintupled over the past 50 years. 65 billion land animals are being slaughtered every year for food consumption. One third of the global grain production is fed to animals for fattening while 1.8 billion people worldwide suffer from hunger and starvation. Can there really be a solution to all these problems?
H.O.P.E. is a life-changing documentary uncovering and revealing the effects of our typical Western diet high in animal-based foods. It contrasts the limited interests of the pharmaceutical and agricultural industry with the all-encompassing interests of living beings on this planet and with the power of responsible consumer action. H.O.P.E. is an urgent call to action to all of us to commit to a change towards sustainability and safeguarding our living environment.

Horizon investigates the idea that the best way to lose weight successfully is a personalised approach, diets tailored to our individual biology and psychology. In a groundbreaking experiment, Dr Chris van Tulleken and Tanya Byron join a team of experts to put 75 overweight volunteers on diets designed to tackle the specific reasons why they eat too much. The volunteers are put through a series of tests at a residential clinic to understand how their genes, hormones and psychology influence their eating behaviour. They are then put on the diets the experts believe are best suited to them. Can science succeed where other diets have failed?

It is time to see if personalised dieting will work in normal life. The volunteers have been given one of three diets to follow - based on their genes, their hormones and their psychology. But now they are back at home, trying to stick to their personalised diets with all the stresses and temptations of real life. Dr Chris van Tulleken and Professor Tanya Byron discover how our genetic makeup can make temptation difficult to resist, how understanding the brain reveals what makes us comfort eat and what science can tell us about why we make disastrous food choices.

So far the volunteers have successfully been losing lost weight, but now the honeymoon period is over. It is the final two months of the diet, and their minds and bodies are fighting back. Dr Chris van Tulleken and Professor Tanya Byron find out if the new personalised diets will help them stay on course, and the experts reveal the scientific secrets to permanent dieting success.

Boxing, 'the poor man's sport', has long given kids from America's roughest neighborhoods an opportunity to escape violence with violence. But with success in the ring comes new fights for which there is no training: champions are made and broken in the blink of an eye, and young men thrust into the spotlight are often ill-equipped for the fame, fortune, and hangers-on that accompany a title belt". And for many, the toughest bouts are fought during retirement, when health and financial issues begin to mount. Built around the stories of heavyweight legends as Mike Tyson, Evander Holyfield and Bernard Hopkins, We will examine their lives in and out of the ring.