When the old Clark bridge at Alton, Illinois, became less fit for carrying traffic across the Mississippi River, a team of designers and engineers was called in to apply its knowledge of science and art to build a new bridge. The team faced numerous challenges. How could team members construct towers that would support the weight of the bridge, road, and traffic load? build a bridge while not interfering with river barge traffic? design a bridge that would be within budget, aesthetic, and safe? In this two-hour special, NOVA tracks the work of engineers, construction crews, contractors, surveyors, and project managers as they build the new Clark bridge from the ground up.