On September 11th, 2001, four hijacked airplanes struck the heart of America. At 8:46 am, New York time, the first airplane crashed into the World Trade Centre -- an attack whose global consequences still reverberate to this day. As early as 1999, Osama bin Laden devised a plan to use civilian aircraft as weapons. The targets were chosen for their symbolic significance to the USA: The World Trade Centre was an economic hub, the Pentagon was the military nerve center, and the White House was the center of political power. But how could the attack manage to succeed? Months before the attacks, the CIA had crucial leads - including the names of known terrorists. Yet they failed to put the puzzle together. This documentary retraces the attacks of September 11th, 2001 in precise chronological order - in the air, at Ground Zero, in newsrooms and in the centers of power in the USA.