• On Sunday, 1.3 million viewers tuned in to watch “Leaving Neverland,” HBO’s explosive Michael Jackson documentary, during its two-hour premiere, according to Nielsen.
  • It’s the third-most-watched documentary premiere for HBO in the past decade, behind “Going Clear” and “Bright Lights,” according to The Wrap.

“Leaving Neverland” has already secured a huge audience for HBO.

Part one of HBO and director Dan Reed’s four-hour documentary, which details allegations of child sexual abuse against Michael Jackson, was viewed by 1.3 million people during its premiere on Sunday, according to Nielsen, The Wrap reported.

Part two of “Leaving Neverland” aired on Monday, and Nielsen will release its viewership numbers on Tuesday.

The Wrap reported it’s the third-most-watched documentary premiere for HBO in a decade. It follows the premieres of the 2015 Scientology doc “Going Clear,” which had 1.7 million viewers, and the 2016 Carrie Fisher and Debbie Reynolds doc “Bright Lights,” which had 1.6 million viewers. But including all on-demand and digital platforms, “Leaving Neverland” was viewed by 1.7 million.

In "Leaving Neverland," two men, Wade Robson and James Safechuck, say they were in sexual relationships with the pop singer when he was at the height of his fame in the late 1980s and early '90s and they were young boys.

Both parts of "Leaving Neverland" are available to stream on HBO Go and HBO Now.

Read more of Business Insider's coverage of "Leaving Neverland":