A Channel 4 documentary broadcast tonight will offer a unique insight into the lives of offenders facing a lifetime in prison.

'Lifers' talks to a range of offenders at HMP Gartree in Leicestershire, including the first prisoner with a whole life sentence to be interviewed on television.

The film's director, Tim Wardle, said "I spent six months filming in Gartree prison for a Channel 4 documentary about life sentenced prisoners. Despite the inherent challenges of making a documentary in a Category B prison, staff were incredibly supportive and made every effort to allow us full access to their work and the prisoners.

"The filming ultimately succeeded because it was a collaboration; it was an amazing, if occasionally tough, experience but I feel it's greatly improved me as a film-maker."

HMP Gartree Governor, Ian Telfer, said "The documentary 'Lifers' was a unique opportunity to showcase the journeys of certain men in our care. It allowed a film crew into the very heart of the prison and followed the daily lives and events that make up this indeterminate and often long sentence."

"The documentary team was allowed full and unrestricted access to capture the very being of Gartree set against a backdrop of sometimes difficult positions and decisions."

Lifers is broadcast tonight at 9pm.