Thanks for your replies and the articles.
My current constraints are the following :
Majority of people on Earth don't have implanted RFID chips, they rather wear a chip as a watch, that identifies them and store their bank account.
Cash isn't used (maybe in some areas, they barter).
Government and corporate areas have very dense surveillance network. At this point i thought about regular cameras (mostly), and drones on every corner. A good number of them can detect IR as well.
Poor areas and wilderness have a low level of monitoring. Also different corporations don't share their databanks (different countries also have to overcome bureaucratic difficulties)
Predicting human behavior, i didnt think about such thing, i assumed that with proper conditioning one can still beat a lie detector.
One corporation has a cutting edge in robotics and AI (at this point i assume that a killer bee still needs remote control, face recognition and image processing is still hard), so other parties distrust AIs to make important decisions and robotic servants.
(Note, the one has the cutting edge in AI thinks in insect like intelligence rather than human like one, IMHO that fits robots more. )
Yes, a luxury prostitute can have access to a good number of dominant people, how much they want to cover this... well if one has a wife, he wants.
Dark net still exists, using it can be punishable, but proving it isn't that easy.
With this constraints, my episode has the following script : (I'd like to note, that doesn't mean it is carved in stone, i also want to write a kidnap scenario)
Night, a car stops in an underground garage, a man gets in, the invisible assassin gets out. Goes up on the emergency stairway to the top engineering level, where they hid his ornitopter. He takes off, and tails a copter to land on a secured building. He can do that, because his IR and radar cross section is pretty low compared to the copter. Stuns the bussinessman and the pilot get out of the copter. The female assistant came to greet them works with him. Use the chip of the VIP and a mask to get in the elevator, that brings him to the 100th floor.
The level (and since it is after work time, the levels above and below) is sealed from people, who don't have proper access codes. Radio signals are also blocked. The two kills four guards with silenced weapons (one of them is drugged already and they have the old trick pretending to be sick, maybe the VIP has eaten something bad).
Cameras are fed with a film that is showing everything is alright. (they have images of the guards)
Then the assassin enters into a conference room, kills the target stuns two other important people.
Knocks out the assistant as well, so she can deny her involvement.
The assassin goes back to the rooftop and takes off with the copter, and use the VIPs access codes to leave the city.
Then trust the copter to autopilot, jumps out and flies away. By the time they realize someone was killed and others knocked out, he is already far away, maybe he was only on hiking, or in a brothel whatever.
(I also thought about weren't it easier to use an anti tank rifle with an image processing program to destroy the limousine of the target? Well i thought about ways to counter this : if they can't have a wide access to the surveillance network, and the target can go without a license plate they don't know exactly which is his car. Kill all VIP arriving to the conference is against the will of the one hired the assassin, also after that much blood, even a high rank personnel would be really investigated. They might also have secure underground tunnels or highways run across the towers)
