Mark finds himself manning a very crowded ER on his scheduled night off, filling in while Doug is out with whiplash and Susan meets with her lawyer. He tries to juggle hunger pangs, 40+ patients in the waiting room and a never-ending stream of traumas.
The ER prepares to take in victims from a plane collision, while Neela and Pratt head out to the crash site where Neela makes heroic efforts. At the end of the day, Neela gets a surprising visit.
Dr. Nate Lennox, a former professor with ALS, is brought in as the progression of his disease is chronicled through his own flashbacks as he is treated by each of the doctors at one point. As Lennox wants to give up, Abby fights to convince him to keep on fighting.
During a paramedic ride-along, Carter is forced to drive the ambulance while fleeing a riot scene and inadvertently runs over a teenage boy. Later, a paramedic is shot by an angry mob looking for the driver of the ambulance. Carol is despondent following Doug's departure. She later discloses that she's pregnant. Kerry is intrigued by an injured pro wrestler and his relationship with his father. Lucy tangles with an Asian family that requests their matriarch not be told of a cancerous tumor. Jeanie turns down dates with both Dr. Baker and Reggie, telling each she's seeing someone else.
Dr. Weaver bends the rules and treats the Alderman's lover for syphilis. Dr. Kovac's patient claims she was sexually abused at a boot camp for troubled youth. Dr. Carter treats a women with a nasty personality.
Weaver, Kovac, and the other doctors work frantically to try to save Jerry and a pregnant Abby, who were both critically injured during the shootout that left the ER in shambles. Meanwhile, Sam tries to escape from her ex-boyfriend and his criminal accomplices as they head north, but things quickly turn violent.
Season Premiere. Moretti's first day is challenging as the ER is inundated with casualties from the peace rally - including Neela. Dubenko faces a crisis in surgery. Abby, Pratt and Morris conspire about how to deal with a shared problem. A new intern arrives unexpectedly, and Gates is reassigned.
Halloween night finds the ER awash with allergic or otherwise incapacitated children. Kerry tolerates a visiting candidate for chief while she waits for the official vote. Romano operates on an 11-year-old girl and finds she's genetically male. Carter leaves Lucy in charge of a dorm party he's supposed to be overseeing, with unfortunate results. Mark learns that Jenn's moving to St. Louis--with Rachel. Mark and Carol treat a pregnant schizophrenic.
A demented patient causes a shootout in the emergency room. After terrorizing people in the ER with a gun, she gets shot by a policeman. She soon dies. Benton later discover her dementia was caused by an aftereffect of his surgery that he and Cleo should have detected. Carter pursues a cute intern.
Just when the ER is understaffed and swamped, two children who were brought in turn out to have full blown smallpox. The entire ER must be locked down. The staff needs to improvise while they battle not only the disease but also frayed tempers.
On a busy Halloween night, Carter and Abby are the only staffers in costume when victims of an apartment building fire pack the ER. Corday takes on a new med student for a surgical rotation - Paul Nathan, who suffers from Parkinson's disease and decided to pursue medicine after being diagnosed. Despite a difficult first day, both professionally and medically, Nathan makes a difficult diagnosis. Romano's rehab lags behind his expectations, and he begins to doubt his role in surgery is no longer an option.
Gates and Morris tend to an elderly man who was assaulted on the street. Sam 's sister shows up unexpectedly. Brenner and Dubenko clash while treating a mother thought to have late-stage cancer. Dr. Morgenstern returns to the ER to assist a former mentor who is seriously ill.
Moretti reassigns Gates back to the ER and treats a couple involved in a car accident. Morris prepares to take his written board exams. Neela is assigned a young genius intern. Kovac plans to extend his stay in Croatia while Abby struggles with single parenthood.
The NCIS team must locate a classified device with the power to destroy Los Angeles that was stolen from a college research facility. Meanwhile, Sam tries to track down a highly sought-after Christmas present for his daughter, and Eric meets Nell’s parents.
After the chief of logistics for a naval weapons station collapses on the job, the NCIS team must determine if this is a terror threat or a stress-induced breakdown. Also, Kensi and Deeks research different honeymoon locations.
Lucy's patient finally gets a heart transplant but does not survive. The transplanted heart will now go to another recipient. Greene interferes in a gay domestic situation. Corday tricked her patient who murdered several women and now he's being transferred to a county jail.
After being shot at, Pratt, Jing-Mei and Elgin are trying to get of their sinking car. Sam took Alex with her while fleeing for Steve, Kovac is considering to go after them. Abby wants to go to bed since tomorrow is her first day as a doctor, but is thwarted by Weaver, whose custody battle might take a dramatic turn. A young drug-dealer is brought in with "a foreign object" in her tunnel of life.
A wounded police officer's teenage son must make a life or death decision. Abby tries to convince a girl needing appendicitis surgery to stay at County, but her fathers wants her transferred to another hospital.
"Freefall" is the best rated episode written by Joe Sachs. It scored 9.1/10 based on 7 votes. It was directed by N/A. It aired on 11/20/2003 and is rated 0.1 points higher than their second-best episode, "Exodus".