Simon Brenner

ER is an American drama series that aired on NBC from September 19, 1994 until April 2, 2009. The series featured a large ensemble cast that changed dramatically over its long run. The main cast was augmented by a wealth of recurring characters and award-winning guest stars.

The original starring cast consisted of Anthony Edwards as Dr. Mark Greene, George Clooney as Dr. Douglas "Doug" Ross, Sherry Stringfield as Dr. Susan Lewis, Noah Wyle as medical student (later Dr.) John Carter, and Eriq La Salle as Dr. Peter Benton. Julianna Margulies guest starred in the pilot as Nurse Carol Hathaway before becoming part of the regular cast.

The first additions to the main cast came in Season 2 with Gloria Reuben signing on as Physician Assistant Jeanie Boulet (recurring character in Season 1), and in Season 3 with Laura Innes as Dr. Kerry Weaver (recurring character in Season 2). In Season 4, Maria Bello signed on as Dr. Anna Del Amico (recurring character at the end of Season 3) and Alex Kingston joined the cast as Dr. Elizabeth Corday. Season 5 saw the addition of Kellie Martin as medical student Lucy Knight.

George Clooney's departure towards the end of Season 5 started a major cycle of main cast changes over the next few years. Season 6 opened with the addition of Paul McCrane as Dr. Robert "Rocket" Romano (recurring character in both Seasons 4 and 5), Croatian actor Goran Višnjić as Dr. Luka Kovač, and Michael Michele as Dr. Cleo Finch. A bit later in the season Erik Palladino joined as Dr. Dave Malucci, and Ming-Na returned to the series as Dr. Jing-Mei "Deb" Chen, reprising a recurring character she portrayed in Season 1. Soon after, Maura Tierney was added as Nurse (later Dr.) Abigail "Abby" Lockhart. Season 8 saw the arrival of Sharif Atkins as medical student (later Dr.) Michael Gallant, as well as the return of Dr. Susan Lewis when Sherry Stringfield reprised her role after having left the series in Season 3.

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