David Icke's reptilian agenda is a fascinating creation, no doubt given from extraterrestrial sources. As a metaphor, simply amazing. 
But what, or whom does conspiracy-baiting serve? The source of David Icke's elaborate construction is key to discerning what is wrong with the picture he paints. Humans make the presumption that off-world sources are always more knowledgeable and better informed--more "worldly wise"--than we in our limited perspective. Certainly they are more experienced in the affairs of commerce among extraterrestrial races and also have been observing our world with a perspective that makes us look like fish swimming in a tank; the presumption that this makes extraterrestrial sources purely objective or in any way altruistic is where the fault lies.
"When you make everything mysterious, you lose touch with what is obvious and you will live in fantasy about everything. That is both pathetic and dangerous for you and your race. Your true state of mind, Knowledge, generally deals with material things in a very down-to-earth fashion and deals with things that are beyond the material in a wholly different way, naturally. There is no confusion of levels or different realms here."
"Humanity does not yet realize how much strength it truly has and the advantages that you have because your religions have been maintained and have not been replaced by a belief in technology. They have not been completely subjugated to the political agendas of ruling nations. Though there has been much corruption, we understand, the power and the presence of Knowledge in humanity remains strong, and its potential for the future is greatly encouraging." 
- Jeffrey Roberts. Collective Evolution, October 17, 2013: The Biggest Secret: Do Reptilian-Human Hybrids Run Our World?