A business contractor with a bad heart gathers his family around him in the ER as he prepares for the end. Dr. Ross helps an asthmatic teenage girl when her mother doesn't have the funds. Carter worries that he may have contracted an STD from Liz. Dr. Lewis treats a teenager with alcohol poisoning. Jenn Greene prepares to move to Milwaukee.

The air conditioning quits on the hottest day in October which, coupled with closed ERs in Chicago's other two hospitals, leads to an extremely hectic day. Dr. Ross treats a six-year-old suffering from a cocaine overdose; Ivan Gregor, the liquor store owner, shoots and seriously wounds a young teenager. Susan's immature sister Chloe drops by, wreaking havoc in Susan's life. Doug picks up a pharmaceutical saleswoman, much to Carol's displeasure.

Carter fumbles his way through his first look at surgery. Dr. Lewis' nemesis, Dr. Kayson, makes her New Year's Day decidedly unpleasant. Chloe announces she's moving to Texas with her boyfriend.

Dr. Anspaugh's 13-year-old son is brought in and Anspaugh asks Mark to look after him. Another old lady who has been raped is brought in.

Greene flies to San Diego when his mother falls and is hospitalized. His concern increases when he finds her acting "completely loony and out of control." To make matters worse, he butts heads with his dad over her care.

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

Abby comes close to breaking down trying to deal with her mother. Dr. Pratt goes for his required paramedic ride-along. Dr. Weaver confronts the man who stole her purse. Dr. Lewis has a teen admirer.

Banfield and Morris go to the coffee shop at 3 a.m. and are served by 20-year-old Debbie who is six-months pregnant. The doctors treat someone with a heart problem and Alex. Chaz must look for a missing 7-year-old boy who saw his sister die.