Meredith Grey and four other first-year surgical interns try to balance life and work at Seattle Grace Hospital.
Interns compete to treat severe injuries, as the emergency room fills with an assortment of patients from the annual bike-messenger race.
Cristina proves to be a difficult patient as she continues to recover; Meredith's mother keeps the hospital staff running in circles; Dr. Shepherd's involvement in the case of a cystic fibrosis patient could delay her departure.
When a series of deaths occurs at Seattle Grace, the uncanny events bring out the doctors' superstitious sides and make Izzie nervous about Denny's surgery.
Leslie asks Dave and Andy to help her catch a teenage vandal; Ann tries to throw a fun Halloween party.