A severe blizzard leaves the ER utterly devoid of patients, leaving the staff free to goof off. In the middle of their fun, a call comes from dispatch, informing the ER of a 40-car pile-up with dozens of casualties. The ER goes from being deserted to capacity. All surgeons are called in. Bob surprises everyone with a quick and life-saving decision. A new doctor, Angela Hicks, arrives just at the right time. Ross and Linda return from the Caribbean just as Carol makes a surprise announcement.

Carter trains one of Benton's new students, Deb Chen. Hathaway has her hands full with an emotionally challenged patient who's obsessed with colors. A sociologist provokes people to measure their reaction times for a study. Kayson brings charges against Susan in the Vennerbeck death, leading Morganstern to question Susan's assertiveness. Benton and Walt hunt for Peter's missing mother.

A busy Dr. Greene goes all day in solving his patients' problems until he encounters the case of a pregnant woman suffering from complications that threaten both her life and her unborn baby's.

Weaver and Susan's feud escalates to the point where Mark needs to step in and fix it. Benton is involved in a parking lot altercation, resulting in a broken hand and Carter replacing him in surgery. Mark cares for an abandoned elderly woman. Susan tries to juggle her work and care for Little Susie. Shep risks his life to bring in a gunshot victim.

Carol and Jeanie try to find a home for a schizophrenic architect. Carter signs Benton up for an interview with Vucelich for a prestigious study. Carter and Harper try to find a place to make out. Jenn and Rachel are involved in a car accident; Mark is thrown for a loop when he learns that Jenn has been having an affair with a coworker. Doug dines with his mother. Susan receives $3000 in the mail from Chloe.

The ER hosts roughly a dozen pregnant women when a sprinkler bursts in the maternity ward. Carter plays tour guide for the visiting surgical intern hopefuls before going through the interview himself. Benton tries to bring a hopeless patient back from the brink of death in a marathon surgery. Jerry tries to convince the others that basketball player Scottie Pippen visisted. Doug visits his father.

Carter engages in competition with new surgical resident-in-training Dale Edson upon learning that residents will be evaluated and graded; only the top ones advancing to second year. It doesn't help that Dale once had a relationship with Harper. Mark flirts with infomercial director Iris. Peter faces the fallout from his altercation with Doug when surgeons begin dropping him from procedures. Shep begins exhibiting uncontrolled hostility, first to a patient being abusive with Carol, then a pedestrian. Susan and Chloe try to reach an agreement regarding Little Susie.