They've been specially trained to sniff out cocaine, cannabis and pharmaceutical drugs, and their role couldn't be more vital to break the cycle of crime in prisons.
Drug detection dogs Jack and Rusty are two of six canines working at HMP Swaleside in Kent, responsible for body searches, prison patrols and cell checks.
The brave pair live with their handler, Daniel Holdsworth, who joined the prison service 10 years ago and now works alongside dogs to help "keep both staff and prisoners safe".
