Almost half of all the seriously mentally ill people in prison assessed as needing hospital treatment are being refused the help they need. In this episode of File on 4, Shell and "Ian" tell us the reality of living with mental illness whilst in prison, why so many people fail to get the crucial treatment they need whilst inside and what impact that has on them. And prison officer "Mike" describes how a shortage of staff and a lack of training contribute to he and his colleagues struggling to help mentally ill prisoners.

File on 4 research shows that the number of seriously mentally unwell prisoners denied a transfer to hospital has tripled in the past decade, leaving hundreds of desperately unwell people living in deeply unsuitable conditions.

Reporter: Annabel Deas

For details of organisations that can provide help and support with mental health, self-harm and feelings of despair, visit the BBC Action Line.