“Leaving Neverland” director Dan Reed sat down at the Variety Studio at Sundance to talk making the Michael Jackson abuse documentary that’s made waves since its debut at the Park City festival.

Reed revealed that it was commissioned as a two-hour piece, but he ended up presenting a five-hour rough cut to HBO.

“It’s four hours because it’s the history of two families over 20 years,” Reed explained. “It’s only by telling that story and threading the theme through the story and building the characters and getting to know the family and getting to know the relationships and understanding what happened that you can really understand why it was that Wade changed his story.”

Watch the full interview above.