20/20 - Season 40

Authorities set up an elaborate sting operation to catch a Houston couple who were allegedly attempting to hire a hit man to kill their exes.

The 2011 disappearance of a 20-year-old Tennessee woman and the ensuing investigation; interviews with the victim's family members and others connected to the case.

Following the life of Nathaniel Newman -- who was born with a cranio-facial condition known as Treacher Collins -- and his family.

An investigation on Christa Worthington's murder in 2002 and the man accused. Christa was stabbed to death with her daughter at her side, and new details on the crime raise questions as to whether the right person was convicted for the murder.

Thirteen siblings are found captive inside a California home; what life was like inside; details on the alleged abuse.

Interviews with key people connected to the case in which two 12-year-olds stabbed their friend 19 times and left her for dead in an effort to appease the mysterious fictional character known as Slender Man.

A man convicted of murder claims new DNA analysis exonerates him of the murder of his former girlfriend's parents; interviews with those close to the case, including the original investigators, and former London detectives who believe he is guilty.

A man is convicted and sentenced to life in prison for two counts of solicitation of capital murder after he and his veterinarian girlfriend attempted to hire someone to kill their exes.

Sexual harassment in the workplace and potential solutions.

A look at the two most important women in Prince Harry's life, his mother, Princess Diana, and his soon-to-be bride, Meghan Markle.

Peter Billingsley, the star of "A Christmas Story," discusses some of the most memorable and beloved Christmas movies of all time, including interviews with the stars, and behind-the-scenes looks at some of the most memorable moments from the films.