While working out the city shots, I used a map converter in Blender to create the city blocks from a real map, and overlaid a procedural building generator on top of each block to quickly create a more realistic density of the buildings, that I could move the camera around in to find good angles.

The subway train shot was created using a mix of Blender’s compositor to make the 3D car in the distance look 2D, and procedural effects to create the halftone pattern outside. I composited these behind the hand drawn background to bring it all together.