Mindhunter Season 2: 9 Serial Killers Confirmed

2. William Pierce, Jr.

William Pierce, Jr. committed at least nine murders after being paroled in 1970, despite numerous red flags that he was likely to perpetrate a violent crime upon being released.

His spree began just a month after being set free, and a mere 10 months after his release, he was arrested for the murders.

Though there was significant controversy over the violent means used to obtain a confession from Pierce - including cuts and burns to his genital area - he was eventually convicted of three murders and sentenced to life imprisonment.

The contentious nature of his confession and the fact that his IQ reportedly "barely broke 70" should make him an intriguing interviewee for Ford and Tench.