Music therapy can change the lives of dementia patients and those who care for them.

Actor Vicky McClure recruits people with dementia to form a dementia choir, and experts from the fields of medicine, music therapy and performance are on hand to nurture and rehearse with them.

This is a story where personal achievements meet breaking science. Advanced brain scans, world firsts and revelatory experiments reveal the miraculous effects that playing and listening to music can have on the brain.

The shared journey culminates in a huge public performance at a major event. Will it all come together on the night?