Ross Kemp spends ten days inside HMP Barlinnie in Glasgow - one of the oldest and toughest prisons in the world. Arriving in handcuffs and processed as a prisoner, Kemp then has exclusive access to every part of this Victorian prison. He works with violent prisoners wielding knives in the jail's kitchen, joins the security team on a cell search in the constant battle against drug smuggling and is confronted with an arsenal of home-made weapons, concealed in eye-watering places. In an attempt to understand why Britain's prison population has doubled in the past 25 years and whether or not prison still works, Kemp explores all aspects of life behind bars. He meets a murderer finishing a life sentence and preparing for life on the outside, and takes on his most challenging interview yet when he comes face-to-face with a sex offender in the prison's E-Hall.