The show deals with how the various states of the United States established their borders, but also delves into other aspects of U.S. history, including failed states, proposed new states, and the local culture and character of various U.S. states. It thus deals with the "shapes" of the states in a metaphorical sense as well as a literal sense.

The show format follows Unger as he travels to various locations, and interviews local people, visits important historical and cultural sites, and provides commentary from behind the wheel of his car as he drives from location to location. Interspersed with these segments are brief historical synopses by notable U.S. historians.