For decades, R. Kelly has been accused of sexual assault. Now, multiple people have joined forces to detail the alleged abuse in a new trailer for the upcoming documentary, "Surviving R. Kelly."

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In the six-hour Lifetime docuseries, which traces the vocalist's childhood to present day, several accusers discuss their relationships with the R&B singer, including his ex-wife Andrea Kelly, who recently spoke out about the abuse she said she endured during her 13-year marriage to him.

R. Kelly’s ex-girlfriend Kitti Jones, R&B singer Sparkle and a host of other women also speak out in the movie.

“There’s a difference between R. Kelly and Robert. R. Kelly’s this fun, laughing, loving guy,” one woman narrates in the clip. “But Robert…is the devil.”

In addition to remarks from accusers, the film also features appearances from celebrities and family members, such as singer John Legend, talk show host Wendy Williams, Me Too founder Tarana Burke and R. Kelly's brothers. Overall, the project includes more than 50 interviews.

“Surviving R. Kelly” will air on Lifetime at 9 p.m. ET Thursday, Jan. 3, Friday, Jan. 4 and Saturday, Jan. 5.