Green Arrow, Volume 5: City Walls

Star City has endured all manner of threats over the years, but when a millionaire wants to bring law and order to its citizens, the entire world is threatened. His spell encases the city in a sphere impervious to even Superman, and the law-bringers are demon behemoths that will kill over the slightest infraction. Green Arrow marshals the most unlikely army of all to save to city, and the world, from the threat. But deals need to be cut, sacrifices made, and the consequences may be worse than the problem!