This paper is about to highlight some of those theories, and on the bases of the 2006 documentary 911 Mysteries Part 1: Demolitions, trying to find some realistic explanation for not really the question who exactly did it, but how. Trying to explore the origins of the molten steel frame, the way how the skyscrapers collapsed, the possibilities that the whole complex was full of explosives. It will be mentioned the buildings’ fire protection system, and last but not least, how did it happen that WTC 7 collapsed the same way as the twin towers’ without any serious damage in the building.