Former Marine Louanne Johnson lands a gig teaching in a pilot program for bright but underachieving teens at a notorious inner-city high school. After having a terrible first day, she decides she must throw decorum to the wind. When Johnson returns to the classroom, she does so armed with a no-nonsense attitude informed by her military training and a fearless determination to better the lives of her students -- no matter what the cost.

By accident, the content of a computer encyclopedia is transferred into the brain of Dexter Riley, a less than average college boy. Because of his newly acquired knowledge he competes in a quiz show between various universities, where he sweeps all the points. A wiz kid from another university finds out about his cheated wisdom and does everything to discredit Dexter.

ER explores the inner workings of an urban teaching hospital and the critical issues faced by the dedicated physicians and staff of its overburdened emergency room.