September morning. You're going about your day when suddenly the unthinkable happens. A huge passenger plane flies straight into a tower of the famous World Trade Center. A short time later, a second plane slams into the other tower. Clouds of black smoke billow from the towers. Will you rush into the buildings and try to help any survivors? Or will you try to escape the broken and burning wreckage falling to the street? Step back in time to face the dangers and difficult decisions that real people had to face on one of America's darkest days.