Inside the enormous efforts made by scientists and government officials to get a COVID-19 vaccine created and distributed to the public in record time.

Rodney Reed attempts to clear his name and overturn his conviction for a 1996 murder.

A woman's seemingly obsessive and threatening messages to an ex precede a stunning twist.

After Boeing's 737 MAX planes were changed and cleared to fly again, "20/20" reports on the aircraft's controversial flight control software and how it mistakenly sent planes into deadly nosedives.

An investigative "20/20" by ABC News and Louisville's Courier Journal takes a deep dive into the evidence in the Breonna Taylor case and searches for answers from the night that claimed her life.

A deep dive into the disappearance of wife and mother Susan Powell and the stunning twist involving her two young sons at the hands of her husband Josh Powell.

A tribute to the legendary "Jeopardy!" host, who battled pancreatic cancer, and his decades-long career in television that turned him into a cultural icon.

A killer terrorizes idyllic California neighborhoods in the 1970s and 1980s, evading authorities as he lives among his victims for over four decades.

James Dailey, who is on death row for the 1985 murder of Shelly Boggio, said Paul Skalnik's lies helped convict him. One of the prosecutors in the case says Dailey received "an appropriate sentence."

John Lennon's close friends and colleagues provide insight into his life and lasting legacy; radio reporters talk about the last interview John Lennon did with them the day he died.

How Paris Hilton, Britney Spears and Kim Kardashian changed Hollywood's fame game and paved the way for a new era of celebrity and social media influencers.

Melanie McGuire insists she's innocent in husband's 2004 killing. Her trial captured the nation's attention after fishermen found her husband's legs in a suitcase.

The ex-wife of former NBA player Lorenzen Wright pleads guilty to facilitating his murder.

A 20-year-old U.S. Army soldier, Vanessa Guillen, is murdered inside a Fort Hood, Texas, armory by another enlisted soldier.

An ABC News special examines his career, from playing Jackie Robinson, Thurgood Marshall, to T'Challa in "Black Panther." His influence was felt far beyond Hollywood, all the way to the White House.

Exploring how the 1963 March on Washington for freedom and jobs began. 

Democratic presidential nominee Joe Biden sits down for his first joint interview with running mate Kamala Harris.

An investigation into why the United States was unprepared for COVID-19, how government and administration officials failed and missed the warning signs, and what the country needs to do to reopen.

Remembering the television pioneer, his life and his legacy as the legendary host of the 'Live' morning franchise for 28 years.

In 2017, authorities reopen the investigation into the 1983 murder of a young Black man in Georgia.

Julius Jones, who was convicted in the shooting death of an Oklahoma businessman at 19 years old, tells his version of events, claiming he is innocent, from death row.

New details regarding the arrest of Ghislaine Maxwell, a longtime companion of the disgraced financier, and hear from the women who survived his crimes.

Interviews with daughters of Karl Karlsen, who nearly got away with murdering his wife and son.

The sting operation to catch a woman in a murder-for-hire plot is filmed for a reality-TV series.

The chilling true crime story of a '85 Chicago Bears legend and the murder of his pregnant girlfriend.

Healthcare workers and medical professionals' extraordinary work on the frontlines, the latest developments on the COVID-19 pandemic and how hard the crisis is hitting the U.S.'s gig economy.

Decades after four bodies were discovered in New Hampshire's Bear Brook State Park, a podcast renews interest in the cold case and helps lead authorities to solving it.

Communities across US take drastic measures to slow spread of coronavirus; How prepared are we to test for the novel coronavirus; The 'new normal' of the coronavirus.

The night a marijuana dispensary owner was kidnapped, tortured and maimed; Cortney Shegerian is the bait in a police plan to arrest Hossein Nayeri; Hossein Nayeri appeals to the jury in his own trial.

The extraordinary chain of events that led to a COVID-19 global health crisis.

After spending almost 10 years behind bars for his former girlfriend's death -- a crime he says he did not commit -- Nicholas McGuffin opens up after his conviction is overturned.

The stars of the hit show look back at the best pitches, the biggest fights, and of course, the greatest money makers and those making the greatest impact with their businesses.

Details surrounding the Jodi Arias murder case, including excerpts from Arias' personal journal and victim Travis Alexander's blog, and new interviews with Alexander's friends and family.

Ted Bundy's longtime girlfriend and her daughter open up about their lives with him.

A look at the elaborate plan Edward Shin hatched to cover up the murder of his business partner Christopher Smith.

A couple was preparing to sell their yacht to move closer to family when they vanished forever. Investigators found that complete strangers to the couple were responsible.

The story of Pamela and Gregg Smart, Gregg's death, and the trial that convicted his wife of accomplice to first-degree murder, among other charges. Close to three decades later, Pamela maintains her innocence.

Pamela Smart talks about the murder of her husband, for which she was sentenced to life in prison.

Interviews with Amanda Berry, Gina DeJesus and Michelle Knight, who made headlines when they escaped their Cleveland kidnapper's home after a decade of captivity.