Dr. Carter leads a walk-out of staff protesting lack of security in the ER.

Corday clashes with new surgical resident Paul Nathan regarding his intervention into the treatment of a sickly young woman, Alison, who has signed a "do not resuscitate" order. Abby wonders about the erratic behavior of her visiting brother Eric, and feels conflicted over a nurse's official complaint against Kovac, Abby's former lover. Meanwhile, Pratt comforts Chen after a patient threatens her, and Corday suspects that an unconscious 14-year-old female patient has been sexually assaulted.

Abby fears the worst when her brother Eric suddenly disappears. He is actually AWOL and she forges Carter's name to obtain his medical records. Carter and Chen treat a frightened Chinese immigrant nanny, Tong-Yi, whom they suspect was impregnated by her employer. Meanwhile, new surgical resident Paul Nathan, who is struggling to overcome a physical disability (Parkinson's disease), tries to help in the emergency room but his fellow doctors do not appreciate his advice to patients. Unable to quench his sexual appetite, Kovac also gets into trouble in his professional life, despite his admirable resolve to find an eye specialist to treat a young gunshot victim. Gallant and fellow medical student Erin Harkins engage in an escalating competition of medical knowledge. And Weaver gets some much-needed good news.

Abby's family nightmare continues as she searches for her missing brother Eric, who she suspects is suffering from serious mental problems. Gallant accompanies her to his military base where they find Maggie, whom Eric turned to for help. When he's transferred, Abby and Maggie go to a Midwestern air force base, hoping to prevent Eric from being court-martialed for being absent without leave. Carter struggles to get out of Chicago to join Abby. Meanwhile, Corday treats a family of patients who, while building a snowman, were severely injured after being struck by a truck driver. She must help the father, Stuart, make a life-or-death decision. Corday also sympathizes with troubled surgical resident Paul Nathan as he struggles with the increasing symptoms of his physical handicap.

Harkins faces a tough call while treating a troubled teen involved in a car crash with her dad; Abby races to stop Maggie from taking manic-depressive Eric out of treatment; and Kovac hits a new low when an elderly woman tips him for his medical services. Meanwhile, an abandoned baby dredges up painful memories for Chen; and Pratt goes to bat for Leon after he's fired from his job for stealing.

Dr. Pratt's disabled roommate leads him to a wounded thief. Dr Carter decides to practice medicine in Chechnya. A doctor makes a pass at Dr. Corday.

A psychotic patient threatens Abby. Dr. Weaver suspects a woman poisoned her own baby. Dr. Romano continues to make rash judgments.

Dr. Carter tries to prevent a grieving gang member from going after vengeance. Dr. Kovac races against time to save a Croatian boy's life. A baseball player gets treatment for a heart problem.