Cast of ER Cast of ER "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
David Dawson (actor) for his role as Smike in Nicholas Nickleby. He was also nominated in 2010 for Best Supporting Actor in the What's On Stage awards for his role as Gethin Price in Comedians. Dawson drew critical acclaim for his portrayal of writer Tony Warren in the BBC Four drama "The Road to Coronation Street". For the "New Statesman" Rachel Cooke wrote: "I think he's going to be a huge star. When he is doing his thing, it is hard to take your eyes off him". "The Daily Express" said "It is David Dawson and some perfectly judged dialogue which brings this