There are amazingly small planes, copters and ornithopters (insectopters?) built by hobbyists these days. I'm certain such a thing will be possible in the next few decades if it isn't yet do-able.
But I think the stylized insect veins on the wings are evidence of someone attempting an aesthetic photographic impact more than mechanical efficiency. To achieve something this size with the performance described would require extreme rigor in the mechanical efficiency department to work at all. On the other hand, a cicada sized drone would be do-able now, I'm sure.
The possibility of building truly tiny drones is barely science fiction at this point. And I suppose one way of reducing the material difficulties would be to use real insect wings, since that design has been worked out over several million years through trial and error, and a common enough raw material. In that case, strike what I said above about the aesthetics.
This may all be wasted effort however. With camera, microphone, and GPS equipped cell phones and computers practically everywhere, in homes and in all public places, in schools, vehicles etc., it just requires a little software magic to perform the same continuous spying and recording function, and is a lot easier and cheaper to implement than trying to build and fly tiny aircraft into positions of interest.