malaysia flight 370. and the moment the mystery begins. >> you have a series of events that appear to be human driven. you have a transponder being turned off. you have an acars system being turned off, you have the plane being turned not once, but at least twice, probably three times. >> and most perplexing, no distress call. >> there are so many ways to notify people that there's a distress. uhf radios, vhf radios. many, many ways. >> none of that happened? >> none of it, for seven hours. >> could the disappearance of mh-370 been deliberate? to answer that question, investigators zero in ton last two men known to be in control of the plane. seen here passing through security on the night of the flight. first officer, fariq hamid was only 27 years old.