Not only is Jessica Spencer the most popular girl in school -- she is also the meanest. But things change for the attractive teen when a freak accident involving a cursed pair of earrings and a chance encounter at a gas station causes her to switch bodies with Clive, a sleazy crook. Jessica, in the form of the repulsive Clive, struggles to adjust to this radical alteration and sets out to get her own body back before the upcoming prom.

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.