Kim Stephens: He's an architect experienced in steel structures. Now Richard Gage is touring the country with a controversial message about September 11. Kopi Sotiropulos: Richard Gage is here to show us why he's calling for a more thorough investigation into the collapse of the World Trade Center buildings. First of all give us a little bit more about your background. Gage: I'm an architect of twenty years, a member of the American Institute of Architects, and have been studying steel frame fire proof buildings for about that long. Kim Stephens: We ask that for clarification because as we get into this, we want people to make sure that you're not just somebody with a wacky idea. You come with some science to you. What is the official reason for the collapse of the World Trade Center towers? Gage: Well we're told that the planes hit the buildings, and there was an explosion and a fire, and about a hour and a half later, in the case of the north tower, the buildings collapsed due to structural weakening, due to the fires. The problem is that we don't have large gradual deformations associated with collapses. And fires in high rises have never brought down a steel frame high rise building at all, ever. And what we have, unfortunately, is the evidence in the twin towers and the third skyscraper to collapse that day, which most people don't know anything about it. We have the evidence of the ten key features of controlled demolition. In the case of building seven, it collapses straight down into its own footprint, at free fall speed, in the first hundred feet. It's dropping, as you can see symmetrically, smoothly, at free fall speed, in the first hundred feet. Two and a half seconds. This is uncanny, there's forty thousand tons of structural steel designed to resist this collapse.