I watched 9/11 Life Under Attack on ITV last night.
I tend to steer clear of "September 11th" documentaries now, I watched so many when the dreadful event was more recent.
But the cinema-verite way in which this was filmed, with amateur footage and the responses of ordinary people caught up just made it so grimly compelling, and the reality of what one was viewing on screen somehow made it seem it couldn't be real, that something like this could surely not be happening.
But it was. Horrible, but unforgettable.