By Jon Silverman
Professor of criminal justice, University of Bedfordshire
Chris Langham - star of television's Help and The Thick Of It - has been has been jailed for 10 months for downloading child pornography from the internet.
What sort of life will the Bafta-winning actor face behind bars?
Langham may end up in a Vulnerable Prisoner Unit
In prison, there's often a distinction between celebrity and notoriety.
Although Chris Langham is reported to have received death threats during his remand for sentencing at Elmley prison in Kent, another famous sex offender, Jonathan King - also held for a while in Elmley - seems to have fared much better.
After release, he described his experience inside as "the best of my life."
Another ebullient high profile offender, Jeffrey Archer - convicted of perjury - survived by observing his fellow inmates with a reporter's eye, offering advice and ensuring that he had powerful "protectors" if needed.
Those convicted of notorious crimes against children, such as Roy Whiting and Ian Huntley are always vulnerable and both have been severely assaulted in prison.
Former prison governor turned criminologist, Professor David Wilson, thinks Langham, too, may be at risk.
"Amongst some prisoners, there's a lot of kudos in bragging that you 'did that Chris Langham', so he'll almost certainly be offered Rule 45 and end up in the Vulnerable Prisoner Unit (VPU)," he said.
No Rule 45 application may be rejected and every prison is supposed to have separate cells and waiting rooms in which those who ask for protection can be processed apart from other newly convicted prisoners.
However, the prison grapevine is remarkably effective and Langham's presence will be known from day one.
The former Chief Inspector of Prisons, Lord Ramsbotham, has pointed out that being within sound of the rest of the prison, even if out of sight, can be intimidatory.
Shouted abuse and threats have driven some sex offenders to self-harm and suicide attempts and, given Langham's troubled background with alcohol and drugs, he will probably be placed on a suicide watch.
At its most stringent, this can mean observation every 15 minutes.
Sex offender programme
Initially, Langham is likely to be held either in Maidstone prison or Elmley, on the Isle of Sheppey, while he is assessed.
Elmley has a VPU and runs a Sex Offender Treatment Programme (SOTP), but given the length of sentence, Chris Langham won't benefit from that.
Langham played MP Hugh Abbot in The Thick of It
The core programme is available to any adult sex offender who has at least nine months left to serve.
The method used - cognitive behavioural therapy - is designed to tackle the distorted patterns of thinking and rationalisation common to many sex offenders.
The extended programme addresses difficulties with anger control and other issues such as managing stress, alcohol or drug abuse.
But a prisoner can't be compelled to go on the programme and those in denial usually refuse.
There are currently over 6,000 people either convicted or accused of sex offences in custody in England and Wales.
With only about 900 SOTP places available, many of those who should get treatment do not and those convicted of internet, as opposed to 'contact', offences are usually at the end of the queue.
Donald Findlater, of the Lucy Faithfull Foundation, says overcrowding is another factor to be considered.
"The priority for the prison service tends to be finding an available bed rather than placing a sex offender where they can get the greatest benefit," he said.
"If an offender does get on a programme, the research shows that their risk of reoffending is likely to be reduced."
For some sex offenders, it is a condition of release on licence to undergo a community-based treatment programme and the Home Office has introduced a version of the SOTP which is designed for those convicted of internet offences.
Chris Langham's few months inside prison are likely to be traumatic and his post-custody life difficult too.