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.

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.