The first part of a new documentary detailing accusations of sexual abuse against the late pop singer Michael Jackson aired on HBO Sunday night, with a second part airing Monday night..

"Leaving Neverland" premiered at Sundance Film Festival in January, reigniting the conversation about the King of Pop's alleged behavior with underage boys. Jackson has been accused of child sexual abuse multiple times, including an accusation involving a 13-year-old boy which did not result in charges, and an arrest on child molestation charges in 2003 which led to a trial and subsequent acquittal.

Here are five things to know about the documentary, which is now streaming in its entirety on HBO Go and HBO Now.

The documentary focuses on two of Jackson's accusers.

The four-hour documentary centers around two of Jackson's accusers, Wade Robson and James Safechuck, who say Jackson began sexually abusing them when they were young boys.

Robson, now 36, claims Jackson began assaulting him when he was 7 years old. Safechuck, now 40, claims the abuse started when he was 10. Both men say they were targeted by Jackson and claim the singer took advantage of them because they were from unstable families. 

Both accusers say Jackson went to great lengths to avoid getting caught.

Safechuck claims Jackson would run drills to see how fast the boy could dress himself quietly to avoid being discovered. Robson claims Jackson asked him to throw his underwear away after a sexual encounter, scared that the then-14-year-old's mother would find it.

One accuser claims Jackson staged a mock wedding ceremony with him.

Safechuck claims he and Jackson exchanged vows and rings in the singer's bedroom when Safechuck was 10 years old. Safechuck says their relationship lasted until he was 14 and claims the singer gifted him jewelry as rewards for sexual acts.

The accusers say Jackson tried to turn them against their parents and women.

Safechuck says Jackson was "very jealous," specifically of Jackson's then-backup-singer Sheryl Crow. Safechuck had developed a crush on her, he says, and claims Jackson would show him pictures of the singer and try to convince him that she wasn't attractive.

The accusers also say he pressured them to testify that he had never sexually abused them after he was charged with molesting a 13-year-old boy. Jackson's supporters and estate have used this 2005 testimony against Robson and Safechuck, saying they "testified under oath that these events never occurred."

Jackson's estate -- and many of his fans -- are denying the claims

Jackson's estate filed a $100 million lawsuit to prevent the documentary's release, to no avail. Instead, the estate recirculated some of the singer's past concerts while the documentary aired. Jackson's nephew, Taj Jackson, has spoken out against the documentary on multiple occasions, defending his uncle and blasting "unfair media coverage." Jackson's estate has called the documentary a "tabloid character assassination." 

Some of Jackson's fans have made death threats against both Robson and Safechuck, as well as the documentary's creators.