A senior public health official who plotted to rape two young girls with the help of their parents was jailed for four years.
Perverted Laurence Knight, 51, talked of having 'serious and horrible' sex with the children while his wife was away in the Middle East.
He swapped online messages with 'Baz' and 'Michelle', arranging to meet and rape their daughters 'Tia' and 'Aimee', aged 10 and 12.
Knight, himself a father-of-two, tried to set up the meeting on the secret 'cheat' phone he used to meet women on adult dating sites while his wife was away.
But Baz and Michelle were undercover police officers who had been tipped off about his paedophile tendencies.
They arrested Knight when he discussed his plans to babysit another girl and said he 'might not be able to control himself' once he was with them.
At the time of his arrest last March Knight was a regional deputy director of communications for Public Health England, a Department of Health agency.
Knight, from Bristol - who no longer works for PHE - claimed what he was doing was only 'fantasy' and he never had any intention of carrying it out.
But a jury at Bristol Crown Court found him guilty of attempting to arrange or facilitate the commission of a child sex offence.
Balding Knight, wearing a dark grey suit, white shirt and a dark tie, sat with his head in his hands as he was sentenced.
The court heard that since his conviction in November he had been kept in prison where he had been attacked and nearly had his earlobe severed.
Recorder for Bristol, His Honour Judge Peter Blair QC, said he was making an example of him to deter others.
He told Knight his interest in child sex was a 'significant and serious shift' from his previous habits of browsing adult pornography and meeting women for sex.
He added: 'This offence by you is one that deserves greater weight to be given to that deterrent, to protect children from individuals with inclinations that you began to show.
'Police had reported observations you made about a real child that you were considering babysitting, and this is why police intervened earlier than they might have done.'
Prosecutor Robert Davies said: 'You are looking at top line offending, that is what was planned and in the context of two children and three adults.'
Mr Davies told an earlier hearing: 'Mr Knight, at the time, was living an outwardly respectable life in Bristol and had a very good job with Public Health England.
'However, he had a secret sexual interest in teenage and pre-teenage girls and incest and he followed up a contact he saw on a photo sharing website.
'He arranged to meet with them in Dartford with a view to their girls aged eight and 10 being seriously sexually abused by the three of them.'
The jury was given a transcript of Knight's email contact with Baz about his girls, in which Knight asked him: 'Have you licked them while they sleep?
'I had a gorgeous girl sleep over recently. Had some Dutch courage so let my hands wander as she slept. Carefully but lovely.'
He told the undercover officers he 'couldn't wait to play games' and 'feel them (the girls) crawling all over me'.
Defending, Kate Brunner said: 'There is no evidence that Mr Knight has acted with paedophilic intent.
'In particular, although there was talk about events relating to real children, the court will know there was no evidence that these events took place.
'Although there was a thorough search of computers, there was no evidence that the defendant had made or sought contact with children.'
She said Knight was considering paying for private therapy in prison and was no longer in denial about his crimes.
The court previously heard he also had a pornography obsession and regularly searched for 'bestiality', 'incest', and 'teens'.
Knight became south west regional communications manager for the Health Protection Agency in 2003.
He acted as its public spokesperson - reporting directly to the chief executive - and remained with them when the agency was absorbed by PHE in 2013.
Knight has been married since 2003 but the relationship had become strained.
He said the communication breakdown and their 'diminished' sex life led to his interest in deviant fantasies.
He told the court he was still with his wife. She was not present to see him jailed.
Knight was jailed for four years, with half likely to be served on licence, and also given a sexual harm prevention order for 10 years.
He will be on the sex offenders register indefinitely.
Government official who plotted to meet up with parents and have 'serious and horrible' sex with their two girls, eight and 10, is jailed for four years Liz Dunphy Mailonline 17 March 2017