20/20 - Season 15 / Year 2015

Melissa Moore, daughter of Keith Jesperson, was a teenager when she found out her father was a serial killer.

Suzy Favor Hamilton's Secret Struggles Despite Success on Track; Olympic Runner Suzy Favor Hamilton Becomes Top Las Vegas Escort; Suzy Favor Hamilton Shocked by Bipolar Disorder Diagnosis.

O.J. Simpson: Inside the Case of the Defense 'Dream Team'; Hear O.J. Simpson Speak For the First Time Under Oath.

‘Shark Tank' Shark Kevin O'Leary Names His Top 5 Sales Techniques; What You Might Not Know About the Business of Mark Kay.

Tennessee Woman Claims She's Victim of Online Threats to Her Life; Young Couple Found Murdered With Baby Alive, Covered in Blood; Woman Denies Wanting Couple Dead Because of Social Media Feud

The so-called "affluenza" case of a Texas teenager who caused a fatal car accident that killed four people and severely wounded another made national headlines in 2013 when 16-year-old Ethan Couch's defense team used an unusual argument during the trial. During Couch's sentencing, a psychologist hired by the defense testified that the teen was a product of "affluenza" -- a term used to describe Couch's irresponsible lifestyle associated with his affluent upbringing -- and that irresponsible parenting had "strongly enabled" the accident, despite the fact that Couch had a blood alcohol level three times the legal limit on the night of the crash.

An Arkansas family re-homes two of its three adopted daughters when the girls' disruptive behavior causes the people to fear for their own safety.

Actress Leah Remini reveals in an exclusive interview with ABC News "20/20" how Tom Cruise was one of the factors that led her to break from the Church of Scientology. "Being critical of Tom Cruise is being critical of Scientology itself… you are evil," Remini told ABC's Dan Harris in a new promotional clip from the interview. Remini, 45, describes how she and her family joined the Church when she was a young girl, built a successful acting career in Hollywood while being a diligent Scientologist, and how she eventually decided to sever ties with the Church.

"As time goes on, you start to lose touch with the real world. The mindset becomes ‘Us against them,'" Remini said. "The decision to leave is you are giving up everything you have ever known and everything you have worked for your whole life." The actress also details her 30-year association with the Church in her new memoir, "Troublemaker: Surviving Hollywood and Scientology." "I feel that people need to understand this has been my whole life," Remini said "I want them to understand how it happens."

Angelika Graswald, accused of killing her fiance during a kayak trip on the Hudson River, discusses the case while behind bars; the 911 call and interrogation video; interviews with two of Graswald's friends; legal roundtable and a kayak expert.

Terrorist attacks on Paris

Barbara Walters interviews candidate for GOP nomination Donald Trump, his wife, Melania, and his children.

Mother and daughter reunion after 50 years, an unbelieveable injustice

Dalia Dippolito, whose conviction for hiring a hitman to kill her husband was overturned, tells her side of the story.

The Searchers: An investigative genealogist helps an army veteran, whose twins disappeared from his life in Korea more than 40 years earlier, find his children.

Former CIA agent Michele Assad and her husband, Joe, plan the evacuation of 560 Iraqi Christian refugees who have been displaced by ISIS.