I know this is probably a bit too late for this example, but this might prove helpful for others wanting to throw a shadow rather than just using a drop shadow. In this picture a drop shadow would just make it look like a cutout sitting on the backgraound whereas a thrown shadow would give the effect of the figures standing in the room.
Copy the layer with the figures and move it to immediately behind the original layer.
Select the contents/outline (in photoshop use Ctrl and click on the new layer in the layers palette)
Fill With Black
Distort to drag it out so it looks to be going back to one side
Reduce the opacity (in eg I used 50%)
Soften with a gaussian blur.
This is the effect you end up with.
Hope this helps someone out.