Apparently, Mossad had operations ongoing inside of Tehran for quite some time. They seem to have taken over all government command sites which are still standing. They've been hunting down and executing IRGC leaders at will, and have complete control of the skies over Iran.
That's what they say, anyway. But, if that is true, then I question how Iran is still capable of sending barrages of missiles into Israel. So, something there is a disconnect with what's being reported and Iran's ability to continue launching missiles.
Also, there are not thousands of people in the streets trying to overthrow the current Iranian regime.
Was this a miscalculation on Israel's part???