Everyone remembers where they were on 9/11—but how closely have we looked at the timeline? In Part One of this two-part series, Alexa takes us back to the lead-up, the morning of, and the immediate aftermath of the World Trade Center attacks. From the air defense failures to insider warnings, strange financial activity, and the perfect vertical collapses of the Twin Towers, this episode sets the stage for everything we were told—and what might have been left out.