Start with a cool scene, like the attempted assassination (glitterati doing a Vienna-style pompous funeral for the old morph, decadence mixed with style and hightech, the exec turning out to be a great freerunner leading the PCs on a merry chase). Then expand your thinking outwards: where does this take place? (find a cool place - a Martian domed city, in the ultra-exclusive cemetery section of a big O'Neill colony overlooking the ruined Earth) And why does it happen? Who is the exec, and why are the PC gunning for him? (he may be a Fall criminal responsible for the death of millions, a political player that must be distracted while the *real* plot occurs among the powerbrokers in the Planetary Parliament, he knows something important and the only way of getting it is to steal his cortical stack) Once you have those details, you can continue expanding the story (who are the PCs - egohunters doing contract work, idealists trying to hit the scum of the solar system, agents for Firewall or just ordinary people who suddenly found themselves equipped with weaponry and a strange half-remembered idea that they are on a mission?) And you can add twists - the target that leads them on a merry chase is not the real exec, but actually a very well trained bodyguard that was sleeved in his body as a decoy. Was there a leak? Or is the whole thing a setup to catch the PCs? This approach also neatly allows you to start in medias res: instead of beginning with "You are all sitting in a tavern as a mysterious stranger approaches..." (which is OK, since the tavern is part of the VPN simspace of Medusan Shield and the mysterious stranger is their boss :-) ) you can begin with the funeral and the fight/chase. Then, as things calm down you can explain a bit more about the backstory. It also allows the players to get to know their characters better.