48 Hours on ID

Three young people with promising futures, Rahul Gupta, his girlfriend, Taylor Gould, and another friend, Mark Waugh, get together for a birthday celebration, then Waugh is stabbed to death in a drunken rage before the night is over.

After University of Virginia student Hannah Graham disappears from a Charlottesville mall, surveillance footage shows her with an unknown man whom investigators identify as Jesse Matthew.

After University of Virginia student Hannah Graham goes missing, investigators take suspect Jesse Matthew into custody and make a bombshell discovery about his DNA.

In North Carolina, Kelli Bordeaux is reported missing after failing to report for duty at Fort Bragg, then a private investigator develops an unusual relationship with a suspect in the combat medic's disappearance leading to the recovery of her body.

Andra and Brad Sachs are shot dead in their California mansion, while their 8-year-old son is wounded by a bullet; investigators cannot pin the crime on a business deal gone bad and look closer to home.

When George Tiaffay finds his estranged wife, Shauna, murdered in her home, he has an ironclad alibi, and it will take a tip from an unlikely source to crack the case; Peter Van Sant reports.

In November 1994, Farah Fratta's body is discovered in the garage of her Humble, Texas, home, and the details of her divorce papers reveal that her soon-to-be ex-husband has a dark side, making him a prime suspect in her murder.

David Temple was in prison for life for his wife's murder when an appeal in 2015 gave him reason to hope; it consisted of evidence his lawyer never received from the state, which could have changed the verdict.

Robert Durst gives an interview to L.A. prosecutor John Lewin touching on the murder of Susan Berman; this conversation may play a role in the case against Durst, who is accused of killing Berman.

In 2001, Missouri newspaper editor Kent Heitholt is found bludgeoned and strangled to death on Halloween night; then, two years later, 19-year-old Charles Erickson has a dream that he and his friend, Ryan Ferguson, participated in the crime.

Two teenage girls are murdered six years apart on San Diego's popular Torrey Pines State Beach, and investigators are stymied for years, querying whether these two cases are connected.

U.S. Army soldier Skylar Nemetz shoots his 19-year-old wife, Danielle, then claims he misfired his rifle and killed his wife by accident.

After Dr. Gilberto Nunez is accused of killing Thomas Kolman, investigators must determine why the dentist would poison a man he says was his best friend.

Some anonymous messaging applications have proved dangerous to teenagers because they can be used by sexual predators; two teenage girls fall into the trap posed by these applications and their online relationships become a matter of life and death.

A serial rapist spreads his net wide, choosing his victims from all over the Denver area; now, he is about to be outsmarted by a pair of female detectives from different police departments.

After Julie Kibuishi is found dead in Sam Herr's empty apartment, police suspect him of killing Kibuishi, even though his father refuses to believe it and leads detectives to one of his son's friends.