National Geographic releases emotional trailer for new 9/11 special, '9/11 Reunited' 

"It's been 25 years and without both of them I would have never made it out."

"That day, someone risked their life to save my life."

These are the emotional words of 9/11 survivors, people who would not have made it through without the help of others.

National Geographic's "9/11 Reunited" tells their stories.

The three-part documentary series, according to the official description, "revisits the deadliest terrorist attacks in U.S. history through the extraordinary human connections formed amid the chaos, courage and heartbreak of that day. Across the episodes, survivors, first responders and witnesses reunite with the strangers, rescuers and everyday heroes who changed, and in many cases saved, their lives on September 11. Many of these emotional reunions take place for the first time in 25 years, providing a rare opportunity to ask long-held questions, express gratitude, and reflect on how those moments have stayed with them for decades."

See the trailer in the video player above.

"9/11 Reunited" premieres August 21 on National Geographic and streams the next day on Disney+ and Hulu.

The docuseries is just one component of Disney Entertainment Television's multiplatform commemoration of the 25th anniversary of the events of September 11.

"Through the storytelling power of our platforms, we will mark this solemn anniversary with programming that honors the victims and their families and helps ensure that the stories of courage, compassion, and resilience that emerged from September 11 endure for future generations," said Disney Entertainment Television Chairman Debra OConnell. "We are particularly proud to be able to shine a light on the work that the 9/11 Memorial & Museum does to honor those who were lost, those who risked their lives to save others, and those who have dedicated their life's work to honoring their legacies."

On September 1, ABC News will air a primetime special led by "Good Morning America's" Michael Strahan that will explore how sports, music, the media, Broadway and comedy helped the country begin to heal in the wake of the attacks. It'll stream the next day on Disney+ and Hulu and re-air on September 11 on ABC, ABC News Live, Disney+ and Hulu.

On September 11, David Muir, Robin Roberts and Diane Sawyer will lead "9/11 Tribute in Light: Live from Lower Manhattan," a multiplatform special in collaboration with the 9/11 Memorial and Museum. It'll honor those we lost on that day, reflect on the lasting impact of September 11 and honor the resilience of survivors, families, first responders and communities forever changed and will culminate with "Tribute in Light," a public art installation which has illuminated the New York City skyline every 9/11 since the attacks.

It'll be live across ABC, Disney+, Hulu, National Geographic, ABC Owned Television Stations livestreams and ABC News Live.

Prior to this special on September 11, ABC News Live will stream a one-hour broadcast from Ground Zero, hosted by "World News Tonight" Sunday and "Prime" anchor Linsey Davis and WABC anchors Sade Baderinwa and Mike Marza.

The Walt Disney Company is the parent company of National Geographic and this ABC station.