Two men have told the BBC they were abused hundreds of times by Michael Jackson, from the ages of seven and 10.
Wade Robson, 36, told the BBC's Victoria Derbyshire programme the singer had sexually abused him from the age of seven and tried to rape him when he was 14.
James Safechuck, 40, told the programme Jackson had sexually abused him "from the age of 10 until around 14".
Jackson's family say there's "not one piece of evidence" to prove the claims.
The two men have also spoken out in the documentary Leaving Neverland.
Warning: This article contains descriptions some may find offensive or upsetting
Asked if the abuse had occurred "hundreds and hundreds of times", both Mr Robson and Mr Safechuck agreed that this had been the case.
Mr Robson told the programme: "Every time I was with him, every time I stayed the night with him, he abused me."
Jackson had fondled him, "touching my entire body", and made him watch the singer performing a sex act, he said.
And then, when he was 14, Jackson had tried to rape him.
'Show our love'
"That was one of the last sexual abuse experiences we had," Mr Robson told the programme.
Jackson had groomed him to believe they "loved each other - and this is how we show our love", he said.
"And then he would immediately follow that up with, 'But If anybody else ever found out what we are doing, you and I would go to jail for the rest of our lives and our lives would fall apart,' he and I would fall apart," Mr Robson told the programme.
"All of this was terrifying to me.
"The idea of being pulled away from Michael - this man, this other-worldly figure, this god to me who had now become my best friend - no way was I going to do anything that would pull me away from him."
Mr Robson said Jackson had told him "I was his best friend and the only person he had ever done these sexual acts with".
"So therefore I was - out of all the boys in the world - the chosen one, I thought," he said.
Mr Safechuck told the programme his abuse had begun with Jackson teaching him how to perform a sex act, at the age of 10.
"Then you start French kissing - he said I taught him how to do that," Mr Safechuck said.
And this had been followed by further abuse and other sex acts.
Find out more
Watch the Victoria Derbyshire programme's full interview with Wade Robson and James Safechuck from 10:00 GMT on the BBC News Channel in the UK.
Mr Safechuck told the programme Jackson had been able to abuse him over such a sustained period of time because he had also successfully groomed his parents.
"There's a long grooming process where Michael inserts himself into your family and becomes a part of your family," he said.
"It takes him a while to build up the trust - it doesn't happen overnight."
And he then "makes a wedge between you and your parents - and he isolates you from everybody else".
"At the same time when you're being abused, a part of you is dying," Mr Safechuck added.
Mr Robson also described Jackson as a "master manipulator".
He had driven "this wedge between myself and my father, [and] my mother and my father" to make it easier for the abuse to occur, he told the programme.
He also said part of the responsibility for the abuse should fall "at the door of all the other people, all the other employees that were around Michael and me and James [Safechuck] all the time, who looked the other way".
In response, Michael Jackson's brothers Tito, Marlon and Jackie, and nephew Taj Jackson rejected the claims in Leaving Neverland - which is broadcast in the UK next week - that the singer had abused children.
Taj said his uncle's behaviour had seemed odd to some but had been "very innocent", adding: "His naivety was his downfall."
And Marlon said there was "not one piece of evidence" to back up the allegations.
Michael Jackson's estate, meanwhile said Mr Robson and Mr Safechuck had previously "testified under oath that these events never occurred".
"They have provided no independent evidence and absolutely no proof in support of their accusations, which means the entire film hinges solely on the word of two perjurers," it said.
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