“Snapped: Behind Bars” revisits some of the most intriguing cases covered on the true-crime juggernaut “Snapped,” featuring exclusive interviews with the convicted women, new interviews that unveil fresh insight on the cases, and experts who look into the psychology of the murderers. Fueled by feelings of remorse and betrayal, protestations of innocence and the need to control their own narratives, the convicted women unburden themselves, in some cases for the first time on camera.