This ER episode eschews the usual "multiple-subplot" format to focus on a single plot line involving little Corinna (Nicolette Little), a seven-year-old victim of a car accident. Inasmuch as the girl has an extremely rare blood type, it is necessary to locate her missing father -- a task that falls to Carter (Noah Wyle) and Lucy (Kellie Martin), who embark upon an odyssey through Chicago that takes them from Wrigley Field to a forbidding back alley. As time runs out for Corinna, Benton (Eriq La Salle) is forced into an unorthodox surgical procedure. ~ Hal Erickson, Rovi