They never met in person, only in an internet chat room. But there three paedophiles plotted the abduction and rape of two teenage girls.

Alan Hedgcock, 42, identified two young sisters he wanted to abduct and rape. In one message to his co-plotters he wrote: “I want them done. I don’t care what you do. I want them done in like Holly and Jess”, a reference to the Soham murders of Holly Wells and Jessica Chapman.

Hedgcock and the two other men were left “drooling” over the possibility of turning their fantasies into reality, Southwark Crown Court was told. The case highlights growing concern about the use of chat rooms by paedophiles to arrange the abuse of children.

Hedgcock, who specialises in creating masks and special effects for horror films and worked on Hellraiser II and 28 Days Later, planned to abduct the girls as they walked through a wood on their way to school.

When asked whether the wood was isolated, he replied: “Yes, there’s a large stretch of them along where they live, their mums always telling them not to walk through there alone, lol [laugh out loud].”

Hedgcock used the name Pholley to discuss his plans with David Beavan, a greeting card salesman, after they met on an internet site. The pair arranged to meet again in the the popular hello.com chat room, where they plotted the abduction and Hedgcock provided pictures of the girls. Beavan then discussed the plot with Robert Mayers.

The men were caught when Beavan went to a police station in January last year to admit what had been going on. Beavan, 42, of Bransgore, Hampshire, was convicted of two charges of conspiracy to rape. He was given an indeterminate jail sentence, with an 11-year tariff, meaning that he cannot be released until the Parole Board considers that he is no longer a risk.

Hedgcock, of Twickenham, southwest London, and Mayers, 42, of Warrington, were also convicted of conspiracy. Hedgcock, who unsuccessfully argued that he was the victim of an overactive imagination, and Mayers were given a similar sentence but with eight-year tariffs. Both were cleared of conspiracy to murder.

In addition, all three men variously admitted 50 sample charges of distributing, making and possessing thousands of indecent images of children.

Judge Geoffrey Rivlin, QC, said that because the men posed a “serious risk of physical and psychological harm to children” they would have to register as sex offenders for life.

Chat-room logs of their discussions were of the “most lurid and disgusting kind”. He said: “You were drooling over the prospect to take these children into the woods and rape them. These logs were further spiced, if that is the right word, by the swapping of pornographic images of young children.”

Outside court, police said that evidence gathered during the inquiry had led to the identification of other men in Britain and abroad who were now under investigation.

DC Dave Adams, of Scotland Yard’s child-abuse investigation command, said: “These three men took a step beyond fantasy and actually identified the children they would target, the location where they would approach them and what exactly they planned to do to them.”

Hedgcock is a co-founder of the Creature Effects special effects agency in Uxbridge, West London, and co-author of Behind the Mask — Secrets of Hollywood’s Monster Makers. The court was told that Hedgcock, who was addicted to child pornography, had said that he wanted to abuse two sisters aged 13 and 14.

Beavan immediately made it clear that he was interested, writing: “I hope you are not a fantasist. I have no limits.” He also confessed to police that he had contemplated killing his wife and had gone through “throttling motions” with a prostitute.

Beavan used the internet to recruit Mayers but lost his nerve when he thought that the authorities might be closing in and betrayed the others.

The case is the second involving paedophiles using internet chat rooms to conspire to rape children. Two men were jailed in 2005 after an Army cadet major discussed a plot to give a schoolgirl a date-rape drug before having sex with her.

Seven steps to identifying a paedophile online

At least 300 children have been sexually abused in the past five years after being “groomed” online, says John Carr, adviser to the children’s charity NCH. The Metropolitan Police arrests on average one man a week for trying to groom children. Girls aged 12-15 are the typical target. Mr Carr says there are seven questions that could indicate a paedophile posing as a child in a chat room:

1. How do you get on with your mum and dad/mates?
A paedophile is trying to find someone lonely and isolated

2. Where’s your computer?
He is looking for computers in bedrooms or other places not easily visible to adults

3. Have you got headphones?
So no one can hear us

4. Can you keep a secret?
He is priming the child with the idea that there are secrets that can be kept from adults

5. Can we go into a private chat room?
For an intimate one-to-one conversation

6. Can you send me a photo?
If a child sends a sexual image this can later be used to blackmail him or her into agreeing to sex. The abuser could threaten to send it to parents or post it on a website for their friends to see

7. You could be a model.
One 14-year-old girl was raped after agreeing to meet a paedophile who posed as a female model, and the male boss of a modelling agency

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