The leader of an online paedophile ring which drew in four female accomplices was branded "warped, wicked, dangerous, devious and manipulative" by a judge today and warned he may never be released from prison.
IT consultant Colin Blanchard, 40, convinced four women - Vanessa George, 40, Tracy Lyons, 41, Tracy Dawber, 44, and Angela Allen, 40 - to sexually assault young children and share the images.
Mr Justice Royce said the father-of-two's interest in child sex abuse was "deep-rooted and long-standing".
He added: "You are warped, wicked, dangerous, devious and manipulative. Your pernicious grooming of women, whose sexual interest in children you stimulate then nurture and feed on, is plain to see.
"You were the hub of the paedophile wheel. Your attempts to paint these women as the predators do not fool me for a moment.
"Even though, once drawn in by you, they played a full part. If there is a predator in this, it is undoubtedly you."
Blanchard could apply for release after serving a minimum nine years imprisonment, however Mr Justice Royce said the decision would be up to the Parole Board.
"The sentence is an indeterminate sentence of prison for public protection. It is in effect a life sentence," he said.
"If the Parole Board is not satisfied it is safe for you to be released, then you will remain in prison for the rest of your days. There would be many who would say that is no more than you deserve."
Blanchard refused to appear in person to be sentenced because he did not want to share the dock with Dawber.
Also sentenced today was Lyons, who was given an extended sentence of seven years - consisting of four years imprisonment and three years on licence - and Dawber who was jailed for four years.
Fellow paedophiles Vanessa George and Angela Allen are already serving prison sentences.
Police smashed the gang when a work colleague of Blanchard found child sex abuse images on his computer in June 2009 and called police.
The net closed in on the rest when detectives identified nursery worker George, mother-of-nine Lyons, community care worker Dawber and ex-prostitute Allen as being the other members.
Blanchard met the women over the internet and convinced them to sexually assault young children and send him the perverted images.
George abused young children at Little Ted's nursery in Plymouth, and Allen and Lyons both assaulted youngsters to please Blanchard.
Unlike the other women, Dawber actually met Blanchard and was in a year-long relationship with him.
She sexually assaulted a child and allowed Blanchard - who convinced her he was divorced - to take pictures of the abuse on his mobile phone.
George was obsessed with Blanchard, telling him she was his "paedo-whore mum" and sending him eight pictures a week.
It emerged in court today that Lyons and Allen had been in regular contact on Facebook - although they had never met in person.
Blanchard, George, Allen and Lyons pleaded guilty to a string of charges of sexual assault and making and possessing child pornography.
The final member of the ring to be convicted was Dawber, who was found guilty in October after a re-trial.
Mother-of-two George, of Douglass Road, Efford, Plymouth, Devon, and single mother Allen, of Nine Acre Gardens, Bulwell, Nottingham, were given indeterminate prison sentences in 2009.
Blanchard, of Yea Fold, Rochdale, Greater Manchester, admitted taking indecent photographs of children, distribution of an indecent image and sexual assault of a child under the age of 13. He had previously admitted 19 other sex abuse charges.
Dawber, of Bedford Road, Southport, Merseyside, was convicted in October of sexual assault, arrangement or commission of a child sex offence and five offences of permitting an indecent image to be taken.
Lyons, of Hewett Road, North End, Portsmouth, Hampshire, pleaded guilty to assault of a child by penetration, sexual assault of a child under 13, causing a child under 13 to engage in sexual activity and three offences of distributing indecent photographs of a child.
Passing sentence, the judge said the case had "caused widespread revulsion and disbelief".
"Your influence, Colin Blanchard, described this morning as Svengali-like, over four separate women so they engaged in sexual abuse of children in such tender years, is frightening.
"It is more extraordinary when one appreciates you never actually met three of them face to face. It is beyond the ken of decent people how any of you could stoop as disgustingly low as you did."
Mr Justice Royce said Blanchard had an "unpleasant interest in bestiality" and had encouraged George to abuse children at Little Ted's.
"You must have known what a terrible breach of trust that was going to involve," he said.
"Vanessa George's actions, with your encouragement, shook Little Ted's nursery and those in Plymouth to the roots.
"The abuse of those children, those parents thought they were safe, has had a major impact on the lives of parents and staff. You then distributed them to Angela Allen.
"The email or text communications between you and Angela Allen and you and Vanessa George are deeply disturbing.
"These and others are sickening to read and reveal attitudes of breathtaking depravity."
The judge said Dawber had an enthusiasm "for pushing the sexual boundaries" but blamed Blanchard for introducing her to child pornography.
Despite Dawber's crimes, her family have remained supportive and were in court to see her sentenced.
The judge described Lyons' online chats with Blanchard about bestiality as "disturbing".
Addressing Lyons, the judge said: "You well knew what Blanchard's perverted interest in children was.
"Having received the child abuse images from him you maintained close contact with him. Your discussions with him are deeply worrying.
"To video the abuse and send it to Blanchard was despicable."
All three defendants were banned from working with children for life and will be placed on the Sex Offenders' Register.
Ann Reddrop, from the Crown Prosecution Service, said: "Colin Blanchard turned out to be an evil man who controlled four women in one of the most sickening paedophile rings this country has seen.
"He encouraged these women to take and share ever more horrific images of the sexual abuse of children. As if that was not bad enough, he encouraged them to physically abuse children to produce those pictures."