2D Animation Assignment

I decided that I wany my animation to be on the the riots which took place in 2011.
Now that I have presented my ideas to Julian I want to start drawing the graphics and finding the images I want in my animation. I'm struggling with the style of animation I want. The images in the background will be of the actual London buildings, they wont be drawn.. Whereas the graphics are going to be drawn which is going to look odd I think.. I'm going to look at some other styles of animation today to see if i can come up with some different ideas.