I believe that all these sightings of aliens (reptilians) must have some sort of basis

To add a bit of my own ideas to this theory....

The dinosaurs existed on earth and faced some sort of mass extinction event. What if there was a dominant humanoid reptile that came to be top of the food chain because of there intellect.

The crocodile/alligator is said to have been around since the dinosaurs, so the theory other dominant species could have survived can atleast be entertained

This species had developed to a pretty high level of technology before the mass extinction event. Seeing the coming change, recognizing a cycle, or just reacting to some sort of catastrophe, these reptilians were forced to go deep underground.

They built huge underground cities connected through massive tunnels and lived for many more thousands of years. The remaining elders finally saw that the earth had finished refreshing and was once again habitable.

To the dismay of the reptilians they no longer survive on the surface as they had become acclimatized to being underground. Knowing the cycles of the earth, the remaining reptilians decided to genetically engineer a surface species that was able to labour and be manipulated.

Seeing this new Earth having different settings they decided on several high intellect bipedal mammals because unlike the reptillian species, mammals must be trained. This was a necessity in creating a good worker. The mammals also displayed good labouring strength and great team work

This is as far as I'm going to go with this for now, maybe I'll write more if I get some inspiration

But I'm leaning towards reptilian overlord controls man through power

Overlords underestimate man and since they cannot rule on this plane (surface) Man becomes "free" to his own devices

Reptilian influence still lingers to those that are lured to darkness. Man becomes controlled again through his own want to control

Man is enslaved to debt, all governments and people are in debt, who is everyone in debt to....not some rich Rockafeller family...no we are in debt to feed and support our overlords