Isolate subject walking through street in normal motion, crowd around him in slow motion

[Tessa5C34]

I'm planning a shot for an upcoming short.  I want my main character to be walking down the street in normal motion, while everything around him is in slow motion.  What is the most practical way to do this in AE?

For reference I have linked a clip from Mr. Nobody.  Here they have sped up the crowd around them, but I'm assuming this effect I'm going for could be done the exact same way but just change the speed settings.

https://www.youtube.com/watch?v=s7K2cQ7_iGc

Any tips would be greatly appreciated.  Thanks.

[Mylenium]

The stuff you referenced is just simple greenscreen work and not even the best one. Otherwise this is 90% planning and has very little to do with AE. In fact with enough people at hand for the crowd and a highspeed camera it could be totally created in-camera with actors moving at different speeds and then cranking up the framerate. Otherwise it's mostly figuring out the different time-scaling to get all the moves aligned. Again, spend your time on planning the physical shoot, not worrying how to process things in AE.

Mylenium

[Tessa5C34]

Thank you for your detailed response!