The Dark Past (1948) When a detective scoffs at his suggestion that an 18 year-old criminal be referred for psychiatric examination Dr. Andrew Collins, the police psychiatrist, tells him the story of his encounter with Al Walker. Walker had a history of violence and killed the prison warden during an escape. He and his gang took the Collins family and their friends hostage but when Dr. Collins learns that Walker has a violent recurring dream, he offers to help him decipher the dream and determine exactly what has driven him to a life of crime and violence.