Stepping through the gates of Blackstream, an all-male prison, to take up position as resident prison psychologist is Louisa Correlli with her expertise about to be tested. Her interest is immediately sparked by Kevin Jones who, like her, is a new arrival, but in prison as a convicted armed robber. Through experiences with the inmates and her fellow prison staff, Correlli becomes increasingly involved in prison life but a growing relationship with Jones threatens to unravel her world.