Linford Christie, Jack Osbourne and Donal MacIntyre experienced life as inmates in one of the "world's harshest prisons" for the new series.

The show, entitled Prisoner: X, also features I'm a Celebrity...Get Me Out of Here! stars Joe Pasquale and Marc Bannerman, actor Will Mellor, author Toby Young and former Coronation Street actress Debra Stephenson.

Britain's former Olympic 100 metres gold champion Christie, who was later banned from the Games after failing a drugs test but has always protested his innocence, spent time in Belize's Central Prison.

Investigative journalist MacIntyre, who is better known for locking up criminals, experienced life in a grim, sparse cell normally reserved for those facing the death penalty in Louisiana State Penitentiary.

Sharon Osbourne's 22-year-old son was extracted from his cell and strip searched in Shelby County Jail, Memphis, while Young, the British author of How to Lose Friends and Alienate People, requested a stab vest in Westville Prison, South Africa, after fearing for his own life.

Bannerman is locked up in Germany, and Stephenson in the US in the Virgin1 series - but none of the celebrities endure life in a British jail.

A spokeswoman for the show said she did not know whether that was because conditions in British prisons were not harsh enough.

Daniela Neumann, Virgin1's director of programming, said: "For the first time ever we will genuinely see these celebrities eat, sleep and shower in the most disgusting prisons in the world.

"These are personal and intimate journeys for people who are used to soft cotton sheets, fine wine, gourmet food and toilet paper - never has the phrase 'being out of your comfort zone' been more true."