Riley Keough and Lily Gladstone were handpicked by book author and series producer Rebecca Godfrey for their roles before her death from cancer in 2022.
The show runners worked directly with victim Reena Virk's father Manjit Virk to tell her story in the miniseries.
Though the real life Rebecca Godfrey died in 2022 before filming began, she worked for three years with show runner Quinn Shephard on the show and the depiction of her played by
Riley Keough. She also gave Shepard her investigative journals on the case and her personal diaries during that period of her life to help round out Keough's Rebecca.
Actress Riley Keough, who plays Rebecca, based her performance on videos of the real life Rebecca Godfrey that she studied and read Godfrey's writings. Godfrey passed away from cancer before she and Keough had the chance to meet.
Casting auditioned over 700 girls across America before deciding on Vritika Gupta for the role of Reena Virk.