"ER" tracks the inner workings of County General Hospital, a Level One Trauma Center where heroic doctors and nurses are faced with life-and-death decisions on a daily basis. The chief of staff, Dr. Kerry Weaver (Innes), a tough and determined administrator, finds herself at a personal crossroads, trying to strike a balance between her life as a doctor and the life she now wants as a woman.
Also on staff are Dr. Luka Kovac (Visnjic), an ER attending physician from Croatia who is searching – sometimes self-destructively – for something to fill the void of his lost family and failed relationships; Abby Lockhart (Tierney), who recently made the professional transition from nurse to doctor, is making a serious effort to turn her personal life around and Dr. Gregory Pratt (Phifer), a brash, third-year resident with a checkered background that won’t stop haunting him.
Recent additions to the ER include Neela Rasgotra (Nagra), a British-Indian medical student who arrives in Chicago after finishing her undergraduate degree in biophysics and molecular biology at Yale. Samantha Taggart (Cardellini) is a nurse and spirited single mother determined to save lives in a place where nothing is taken for granted.
Dr. Ray Barnett (West) has come aboard as a doctor who would sometimes rather be playing in his band than treating patients. He has a way with the ladies and a knack for making things go smoothly, most of the time.