Livvy Haydock investigates the increasing amount of contraband getting into UK prisons, uncovering the links in the chain on both sides of the law. Embedding herself with the criminals who are making 10 times the street value of drugs by selling them behind bars, she meets the key people involved, talks to a serial reoffender who admits he has ‘seen everything’, and learns how drones and corrupt prison officers can be effective means of getting contraband inside. This powerful film reveals more than ‘how it’s done’ from the criminal perspective; it also asks questions about wider prison life, what really goes on inside, and how the rise in technology combined with the lucrative black market behind bars is driving serious violence between inmates – violence that extends to the outside world.