In Florida, the trial of Donna Adelson -- accused of masterminding a hit on her daughter's ex-husband -- is derailed. Hear jailhouse phone calls between her and her convicted son. And in San Francisco, the trial for the man accused of killing the co-founder of Cash App last spring is just around the corner. Plus how to avoid becoming one of the millions who fall victim to fraud.

The music legend once known as Puffy, Puff Daddy and Diddy was arraigned in open court this week. NBC News correspondent Chloe Melas was there. And in a northern Virginia suburb, did a man kill his wife and a stranger so he could be with their au pair? Plus, talking to longtime Dateline producer Dan Slepian about his book, "The Sing Sing Files", chronicling his decades uncovering wrongful convictions.

In Minnesota, arguments over evidence in the run-up to a poison specialist's murder trial, and, in South Carolina, a reckoning for the longtime girlfriend of a convicted killer. WMBF reporter Ashley Boles was in the courtroom for the suspenseful plea hearing. Plus, tips from Today show senior investigative correspondent Vicky Nguyen on dorm room dangers.

In suburban Boston, years after the death of a pregnant 23-year-old was ruled a suicide, the FBI arrest a former local detective for her murder. In Lake County, Florida, a mom on trial for her husband's murder is raising a wildcard defense: her daughter did it. And Dr. Mary Jumbelic answers our question: how can medical examiners reach different conclusions in the same cases?

NBC Boston's coverage of Sandra Birchmore's case

In Utah, Kouri Richins fails in her bid to get her case tossed out. On Thursday Judge John Judge will hear arguments for and against moving the trial of the man accused of killing four University of Idaho students from their college town to the big city. And how to talk to your child about sexting.

An American woman vanishes from Madrid and the prime suspect -- her estranged husband -- tries to get out on bond. In Las Vegas, Robert Telles is on trial for the grisly murder of the man investigating him. And NBC Connecticut journalists dig into the controversial past of Dr. Henry Lee, who testified in the OJ Simpson and JonBenét Ramsey trials.

You can watch NBC Connecticut's Traces of Doubt: The Forensics of Dr. Henry Lee here.

In a town of 4,000 people, a Facebook group of 10,000 asking what happened to a woman stabbed to death. 15 years after thousands of untested rape kits were found, Kym Worthy tells us how she's making sure a backlog like that never happens again. And why are there so many poisonings lately?

If you or someone you know has experienced sexual assault, call the National Sexual Assault Hotline at 800-656-4673 or visit online.rainn.org for more resources.

Keith Morrison looks back on the trial of a woman who killed her bronze medalist husband. Oscar Pistorius, called the Blade Runner after the London Olympics, gunned down his girlfriend in 2013. Now he's out on parole. And a self-defense expert with advice for solo joggers.

You can listen to Dateline's episode about Dave Laut and Jane Laubacher, called The Hometown Hero And The Homecoming Queen, here.