On August 31st, 1997, Diana, Princess of Wales, is involved in a nighttime crash in Paris that leads to her death, the death of her partner Dodi Fayed and driver Henri Paul. On the same day, a phone call in the middle of the night leads Sandi Clark to an emergency room and a tragedy she’s not sure she can handle.

On April 19th, 1995, a bomb is detonated outside the Alfred P. Murrah Building in Oklahoma City. 168 people are killed and nearly 700 wounded in the largest domestic terror attack in United States history. On the same day, Captain Brian Udell is forced to eject from his fighter jet at the speed of sound and fight for survival while lost in the Atlantic Ocean.

On April 20th, 2010, British Petroleum suffers an explosion at its Deepwater Horizon rig in the Gulf of Mexico. Eleven workers are killed and the rig begins to leak millions of barrels of oil, the worst spill in history. On the same day, Kayla Gerdes loses control of a van she’s driving and her life is changed forever.

On May 18th, 1980, Mount St. Helens erupts in Washington state. It’s one of America’s most destructive natural disasters, spreading ash across 11 states, causing the largest landslide in recorded history and destroying all life within miles of the blast. On the same day, 18-year-old South Korean Jechul Ru finds himself caught up in a nationwide protests against the government and the government’s deadly response.

On April 4th, 1968, civil rights leader Martin Luther King Jr. is assassinated at a hotel in Memphis, Tenn., threatening to further strain civil unrest in America. On the same day, Gerry Griffin sits in the control room at NASA, struggling to guide a damaged Apollo rocket into space.

On April 20th, 1999, Dylan Klebold and Eric Harris walk into Columbine high school and begin shooting classmates and teachers. They murder 13 and injure nearly two dozen more before committing suicide. On the same day, Kathleen Tyson, who is HIV positive, walks into a courtroom to fight for the right to breastfeed her infant son, which the state of Oregon claims will kill him.

On February 11th, 1990, Nelson Mandela is released from prison after being confined for 27 years as a political prisoner. His release is a global event and signals the beginning of the end of apartheid in South Africa. On the same day, 24-year-old Danny Johnson cuts through the final bar of his cell and escapes from a prison in Joliet, Illinois, unsure where he’ll end up.

On February 1st, 2003, the Space Shuttle Columbia breaks apart on its 28th mission while re-entering the atmosphere. The seven-member crew are killed almost immediately, the first astronaut fatalities in almost 20 years. On the same day, Megan Sukys travels to see her dying father and come to terms with what his life meant.

On September 11th, 2001, four commercial airplanes in America are hijacked by extremists and crashed into the World Trade Center, the Pentagon and a field in Pennsylvania, becoming the most deadly and devastating terrorist attack in history. On the same day, whale researchers off the Atlantic coast begin exploring a phenomenon that hasn’t existed for decades.

All episodes available April 20, 2017