The story is based on a novel of the same name by Mara Leveritt and comes from the real story of the Gang of West Memphis. The story behind an appalling murder in Arkansas in 1993: on May 5, 1993, three 8-year-old boys from a small village in West Memphis, Arkansas disappeared, and three "bad youth" young Jesse MissKelly (Jessie Misskelley Jr.), Damien Damien Echols (Damien Echols) and Jason Baldwin (Jason Baldwin) were identified as suspects and held for 18 years. In August 2011, after 18 years in prison, the West Memphis trio was released. Reese Witherspoon, who plays the mother of a victim in the film, at first believed in the results of the police investigation, but as the case went on, she began to doubt the fairness of the case. Colin Firth, on the other hand, plays the role of a private investigator who is a supporter of the defendant in the first place and enumerates crucial evidence through investigation. He has been supporting the defense free of charge, so he suffered at that time.