An accused killer's surprise defense. A pharmacist on trial for poisoning. And a medical examiner's strategy for cracking cold cases.

In Tennessee, the defense attorney for a man accused of stabbing his girlfriend to death makes an unexpected admission. In West Virginia, a pharmacist already serving time for scamming her family and friends out of millions is back in court. This time she's accused of murdering her husband. And Alec Baldwin sues the prosecutors on the Rust trial. Plus, a medical examiner discusses the art of investigating cold cases. 

Find out more about the cases covered each week here: www.datelinetruecrimeweekly.com