An alleged "murder dentist" in Colorado. Hawaii husband takes the stand at his second murder trial. And Keith talks about his latest podcast series.

A dentist already facing murder charges for allegedly poisoning his wife is back in court. This time he's accused of plotting to murder four other people from behind bars. In Honolulu, a man accused of murdering his wife's acupuncturist ex-lover takes the stand in his own defense. More from the courtroom ahead of the trials of Karen Read and Bryan Kohberger. Plus, Keith Morrison talks about the unusual clue that broke the case wide open in his latest podcast series, "Murder in the Moonlight."