Our lifespan is increasing by 2.5 years every decade - and a third of all babies born today can expect to live to 100. But living longer can come at a cost. Old age itself brings with it a range of debilitating illnesses, many of which are the result of accumulating damage during our lifetime. Three diseases in particular have become the main killers in the developed world - cancer, heart disease and dementia. But a revolution in bio-medicine is now offering new hope for the treatment of these ailments, and the potential to extend our lives still further. Methods such as gene editing and stem cell therapies are transforming the way medicine can conquer disease today. "How to Live Longer" counts with the guide of the Nobel laureate Sir Paul Nurse, for whom the big question isn't just what science can do to fix our bodies and extend our lives, but whether it's right to use all the tools and techniques available.

In the fourth episode of the series, an unexpected confession casts doubt on Steven's role in the murder case, but the new suspect gives conflicting accounts of what occurred.

In the fifth episode of the series, as Steven's trial begins, his attorneys argue that law enforcement officials framed him and were negligent in not pursuing other leads in the case.

In the last episode, in the years after Steven and Brendan's very public trials, the various members of the Avery family struggle to mend their broken lives.

In the ninth episode, Steven's trial is over, but a new one is just beginning. Will the jury find the suspect's confession or his conflicting statements more believable?

In the eighth episode, after two long days of closing arguments, the jury deliberates. Steven's fate hinges on whether the jury believes police misconduct may have occurred.