Author Terry Pratchett has early-onset Alzheimer's, meaning he faces a world without words. He explores some cutting-edge science to reveal more about this illness.

Best-selling author Terry Pratchett has early-onset Alzheimer's, a disease he is prepared to tackle head-on.

In the first of a two-part series, Terry confronts living with his uncertain future and facing a world ultimately without words. Following Terry's progress through his first year with Alzheimer's, this programme explores some cutting-edge science and weird treatments to reveal what it is like to be diagnosed with this terrifying illness.