One by one, he stalked the young girls online, insinuating himself into their lives through their social media and email accounts and posing alternately as a young boy or a girl.
For six months in 2015, Alexander Jordan Miller, who at the time was a 19-year-old Elk Grove man, would befriend his victims online. He would find a dozen girls nationwide who ranged in ages from 11 to 15, and convince them to send a nude photo of themselves.
And then they were trapped.
"Once Miller obtained a nude photo of a victim, he used that compromising image to coerce his victim to provide more and increasingly graphic videos of their own sexual abuse," federal court documents say, describing a series of online threats and extortion to have the girls perform sex acts on camera or face the embarrassment of him sending the original nude photo to their parents or friends.
Sometimes the abuse included demands that they use a hair brush or curling iron to abuse themselves, or that they follow his demands whether their parents were nearby or they were at a grandmother's home, court filings say.
"I hate my life," one victim wrote to Miller as he was demanding she abuse herself on video, the documents say. "I hope u enjoy this video.
"I'll have to remember to make one when I kill myself."
On Tuesday in federal court in Sacramento, Miller, now 22, learned the price of his online exploitation of the girls: 22 years in prison.
"What they had to go through is, in effect, a life sentence for them," U.S. District Judge John A. Mendez said in sentencing Miller. "They're going to be in counseling for the rest of their lives.
"They're getting more than you are."
Mendez described Miller's actions as "a horrible crime beyond description," but noted that he needed to craft a punishment recognizing that Miller will some day be released from prison and must fit back into society.
The sentence matched the recommendation from both prosecutors and probation officials, who acknowledged that they were not seeking the maximum of 30 years that could have been imposed.
Miller's attorney, Rachelle Barbour, made an impassioned plea for leniency, asking Mendez to impose the minimum 15-year sentence allowed and to take into account Miller's youth, immaturity and the fact that he has expressed deep remorse.
"When you talk about 15 years, this is not a slap on the wrist," Barbour said. "This is a huge sentence ...
"He is a very young 22 years old. He hurt them. He feels, clearly, terrible."
Miller, a slight man who stands 5 feet, 10 inches and weighs 140 pounds, stood wearing glasses and orange jail garb next to Barbour and wept quietly for much of the hearing.
"I want to say that I'm very sorry," Miller told the judge before sentencing. "They should never have had to experience any of this."
But he could not overcome the pain his victims described in letters read by Assistant U.S. Attorney Brian Fogerty in court.
A letter from the mother of one victim said the girl no longer will allow photos to be taken of her, even her senior high school pictures. One young victim wrote that "he made me undress and do unimaginable things."
"He left me traumatized and completely broken," she wrote. "I fell into a deep and dark hole.
"I fell into a deep depression I didn't think I would ever get out of."
Prosecutors described Miller in court filings as a cunning predator who surfed the internet looking for just the right kind of victim, "girls who were young enough to make the mistake of providing a nude photo and incapable of resisting his coercion."
"Miller’s extortion scheme required premeditation and a persistent willingness to make young girls suffer," Fogerty wrote in a sentencing memorandum. "Rather than physical force, he used fear to compel these girls to create these videos.
"The children begged him to stop. They cried. However, Miller, then a 19-year-old man, dominated these children's lives. He could reach his victims anytime day or night, and he required them to satisfy his demands immediately."
One victim "repeatedly harmed herself," court papers say, others contemplated suicide.
A search warrant affidavit filed in the case says the scheme began to unravel when the mother of one victim found out what was going on and messaged the perpetrator — known to her as "Ryan" — on Instagram and told him she was going to the police.
Miller's activities ceased when the FBI showed up at his door to ask about his online pursuits, court documents say, and he was indicted 14 months later in April 2017 on five counts of producing child pornography and one count of possession of it.
Five months later, Miller pleaded guilty to one count of producing child pornography and has since expressed remorse for his actions, offered to apologize personally to his victims and sought to assure them that he never posted any of the images of them online, his lawyers say in court filings. Those documents describe Miller as "good kid" who became entangled in the online world of pornography starting at age 13.
"This sheltered and geeky thirteen year old, who was bullied in middle school, shy, and unpopular with girls, and isolated at home, was shocked by this social world online," Barbour wrote. "Of course, he was also excited by the prospect of social and sexual experiences that he would never have in real life.
"Alex was approached online by teenage girls, and he was approached by adult men who tried to manipulate him into performing sexually. A friend taught him that he could get more images by threatening to post the ones he already had."
His lawyer argued that Miller had "no real world outlet for his teenage hormones" as he used the online chat room site Kik to explore the web.
"Alex came of age when Kik was brand new, and no one was talking to teens about the new challenges and dangers from this unregulated social media, outside the view of their parents," Barbour wrote. "The teenage brain, especially the very young teenage brain, is compulsive, narcissistic, and thinks short-term.
"The teenage boy brain is especially vulnerable to the hazards of growing up in a society of hyper-sexualized images and super-masculine expectations."
Prosecutors were not swayed by the argument, noting the huge disparity in age of some victims, who were identified in court filings as "Jane Doe."
"His victims were not his peers," Fogerty wrote in his sentencing memorandum. "Miller had graduated from high school at least a year before any of the conduct described in this memorandum occurred. "He had a driver’s license and a job.
"He was old enough to vote. He had the cognitive tools to function as an adult. His victims did not. Jane Doe 2 was not even in high school. She was unable to work, drive, or even purchase a ticket to a PG-13 movie.
"It is hard to overstate the disparity in development and life experience that existed between 19-year-old Miller and 11-year-old Jane Doe 2. And that is why he chose her."
Mendez agreed to recommend that Miller be sent to a federal prison in Safford, Ariz., where he can receive counseling while incarcerated, and ordered him to spend 10 years on supervised release after he serves his time.
The judge also agreed to a last request from Barbour, who asked Mendez if Miller, by then red faced and emotional, could hug his grandfather before being sent off to prison.
"Yeah, he can hug his family," Mendez said.