"Chaos Theory"
Season 9, Episode 1
Air date September 26, 2002
Written by Jack Orman & R. Scott Emm
Directed by Jonathan Kaplan
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Chaos Theory is the 1st episode and the 9th season premiere of "ER"


NBC Description

NEW SEASON BEGINS AS E.R. STAFF ABANDONS HOSPITAL LEAVING SOME DOCTORS QUARANTINED AFTER DEADLY ILLNESS IDENTIFIED: Resuming from last year's season finale, the hospital remains in lockdown while the Center for Disease Control probes a mysterious and deadly illness that leaves Dr. Carter (Noah Wyle), Abby (Maura Tierney) and others quarantined.

While Dr. Lewis (Sherry Stringfield) initially is left alone and fights to save one patient, Carter and Abby grow resolved to their romantic fate over the next several days as they idle away their time inside the hospital with Drs. Chen (Ming-Na) and Pratt (Mekhi Phifer) and veteran patient Stan the Can (guest star Harrison Page).

Meanwhile, newly widowed Dr. Corday (Alex Kingston) struggles to adapt to her new medical practice in her native England while over-shadowed by her attentive parents (guest stars Paul Freeman and Judy Parfitt). Laura Innes, Goran Visnjic, Paul McCrane and Sharif Atkins also star.


After a young girl is brought into the ER with a potentially serious and highly communicable disease, the Centre for Disease Control orders the entire hospital to be evacuated. Everyone that is except the staff who came into contact with her including John Carter, Abby Lockhart, Pratt and Jing-Mei Chen who will have to spend two weeks quarantined in the ER. Abby and Carter start a relationship. While evacuating patients by helicopter, Dr. Romano has a serious accident. Elizabeth Corday has returned to London to work in her father's hospital but is finding it difficult to adjust to her new environment.



  • This episode was also known as Unknown Origin


Dr. Robert Romano: Hello, who is this? You like your job? You wanna keep it? Well, then you tell your chief of staff, you know who that is? Good! Well, you tell "Jonesy" that Robert Romano is sending over four critical patients all of whom, I expect to be treated like his own mother but without the inappropriate touching.


Dr. John Carter: You could get a tattoo.

Nurse Abby Lockhart: I could get "Carter..."

Dr. John Carter: Yeah.

Nurse Abby Lockhart: ...Sucks."

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