From common painkillers to new wonder drugs, all medication was once a leap into the unknown.

This three-part series takes us to the vanguard of medical science at the National Institutes of Health in Maryland to meet scientists and the patients taking part in clinical trials.

Tonight we meet oncologist Terry Fry, a leading leukaemia research doctor, and mum-of-three Anita, who’s trialling a treatment that uses her own immune system to fight skin cancer.

It is as moving as it is mindblowing – with brave patients knowing their treatments are more likely to help future generations than themselves.