This was a lot of fun to do (I worked with the writers on this segment - Series 3 - Episode 10 "Brutus" first shown 24th November 2006). Based on the Crowd Dynamics software tools I developed over the last 20 years we developed a scenario where real-time video coupled with crowd dynamics could highlight unusual and suspicious activity in a crowd. Although the scenario is an assassination we use this specific technique to identify early warning indicators for crowd problems at festivals and mass gatherings.
Currently we teach video operators how to use this technique for crowd monitoring - click here for further information