Shifting Equilibrium is the twentieth episode of the fifteenth season of the NBC medical drama series ER . It premiered on March 19, 2009.
|Season 15, Episode 20|
|Air date||March 19, 2009|
|US viewers||9.28 M|
|Written by||Lisa Zwerling|
|Directed by||Andrew Bernstein|
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I Feel Good
Cast and Characters
Justina Machado as Detective Claudia Diaz
Leland Orser as Dr. Lucien Dubenko
Laura Cerón as Nurse Chuny Marquez
Gil McKinney as Dr. Paul Grady
Julian Morris as Dr. Andrew Wade
Troy Evans as Frank Martin
M.C. Gainey as Darrion Walters
Diego Klattenhoff as Jay
Christopher B. Duncan as Matthew Graham
- The music number played at the end when Neela is leaving and joining Ray , is the same music number that plays for Dr. Greene in Orion in the Sky when he is leaving, and for Abby when she is dancing with Frank and leaving as well.
- Although listed in the opening credits, Angela Bassett does not appear in this episode.
- The title of the episode relates to the name of the medical facility where Neela arrives at the end of the episode - "Lechatlier Medical Center." In chemistry, LeChatlier's Principle states "if a system at equilibrium is disturbed, the system will, if possible, shift to partially counteract the change."
- Cancel Bear, The (March 20, 2009). "Thursday Ratings: Down To The Wire ". TV by the Numbers. (May 24, 2015).