As a hijacked plane hits the north tower, we follow the first firefighters on the scene and their race against time to rescue the civilians trapped above and witness a businessman trying to save the life of a badly injured stranger. As a second plane hits the south tower, no doubt remains: America is under attack.

As an announcement tells people to remain where they are, those in the south tower watch with shock as the north tower burns after being hit by a hijacked plane. When the second plane hits, civilians in the south tower have to find a way to escape from the top floors to safety. Paramedics at street level face an onslaught of both the badly injured and casualties. They race against time to save lives.

After two planes hit the World Trade Center, a day of terror continues to unfold. Flight 77 crashes into the Pentagon, while Flight 93 is hijacked and diverted toward Washington D.C. We follow the heroic stories of military personnel in D.C. and the United 93 passengers as they desperately struggle to save lives. Back in New York, the south tower collapses, unleashing a new wave of casualties.

Survivors become separated when they are engulfed by a gigantic dust cloud after the fall of the south tower. We follow them as they wrestle with the trauma of their experiences and desperately search for missing loved ones. When the dust settles after the collapse of the north tower, we witness emotional reunions and heart-breaking losses.

First responders look at the vast pile of debris at ground zero and wonder how anyone could still be alive. But one group of firefighters who were inside the north tower as it collapsed managed to survive miraculously. Now they are trapped, and as they radio “mayday” for help, other firefighters must race against time to locate and rescue their “brothers” in a dangerous and unstable ocean of rubble.

In the aftermath of the towers collapsing, two former Marines and an ex-paramedic head to ground zero to search for survivors. Together they stumble upon two Port Authority police officers trapped 50-feet beneath the rubble. Putting their own lives on the line and against all odds, the volunteers manage to pull off one of the most daring and inspiring rescue stories of the day.