He later told police he was not a paedophile himself but felt "power within the community"; he told them he became popular. People deferred to him and asked for advice. He was important. To gain further respect he often assumed the identity of an American paediatrician with access to children.

Graham, 23, has admitted 13 charges of child pornography, child abuse and "hurtcore" (sexual torture) relating to a network of sites he set up on the darknet, a hidden internet only available with the right software.

He ran the sites between 2011 and 2014, beginning when he was just 18 and a VCE student at Epping Secondary College in the northern suburbs. He operated from his bedroom in his parents' house in South Morang using various overseas servers. He was arrested in 2014 after a joint FBI/Victoria Police probe.

Graham admitted all charges last year and faces a sentencing hearing this week in the County Court.

Judge Michael Tinney said Graham's crimes were "unusual and prolific." He said one charge – of advising a Russian man on how to abduct, rape and kill a five-year-old girl, and film it – was unprecedented.

"That is an offence I have no knowledge of seeing before."

The court heard it was not known whether the Russian man had acted on Graham's advice to kill the girl..

Another charge relates to encouraging a British man to rape a seven-year-old girl with muscular dystrophy. The girl was in the man's care. Graham offered advice to the man on how to conceal his identity in a video. "It's much better to ask a question now rather than spend the rest of your life in prison," he told him.

Graham sat with his head in his hands as this and other gruesome admissions were read out in court. His mother, father and sister were in court for the first time since he was arrested but did not acknowledge him.

Much of the detail of the images and videos he administered, shared and facilitated are too awful to print but all involve babies or toddlers. In one set of pictures a female toddler had the word 'rape' written on her stomach. Others involved animals. The court heard he had taken or acquired non-sexual pictures of his neighbours' young children.

Graham was closely linked to Peter Scully, the Australian paedophile who is now facing murder, rape and human trafficking charges in the Philippines. Scully made a four-part video called Daisy's Destruction in which he and his Filipino girlfriend allegedly sexually tortured an 18-month-old girl. Graham admitted procuring the video series as a "stunt" to get traffic towards his own websites.

At its peak his most popular secret website had up to 400,000 visitors per day. Graham told police he wanted to be the "biggest and the best." But he also taunted the FBI while they were chasing him and at one point, in 2013, tried to make a deal where he would tell them everything he knew in return for immunity and $US50,000. Police consider him a non-contact offender. He never touched a child. He just built a network so that others who do could be seen.

When his parents' suburban home was raided in 2014 police seized his computer tower, laptop, mobile phone and two USB sticks. Even after a magistrate ordered he reveal the passwords, he refused. He finally relented, and they got in. The two encrypted USB sticks remain unopened however; the court was told Graham had forgotten the passwords and FBI agents had not managed to break through the encryption.