Anthony Edwards says it's easy being Greene.
The actor, who left ''ER'' six years ago, said in a telephone news conference Monday that he had no problem getting back into the swing of things while reprising his role as Dr. Mark Greene for the Nov. 13 episode of the NBC medical drama.
Said Edwards: ''It was really like going back to high school, in the best way. It was like going back to your favorite class and having your favorite teacher. ... It took about a half an hour -- and after about a half an hour, I really felt like I'd never left.''
Dr. Greene, who died of a brain tumor at the end of the 2002 season, appears in flashback scenes with former County General Drs. Kerry Weaver and Robert Romano (portrayed by Laura Innes and Paul McCrane, respectively).
He also has an encounter with series newcomer Dr. Cate Banfield (Angela Bassett), an attending physician at the hospital, after she brings in her sick son. The flashbacks are interwoven with a present-day story line that shows Banfield helping in the rescue of a young girl who falls into a lake.
Discussing the character's passion for medicine, Edwards said: ''When you get on an airplane, you hope that the pilot really loves flying -- I think that's what Greene had. You do want to go to a hospital and have a good doctor who loves being a doctor there.''
Edwards' appearance comes in the 15th and final season of ''ER,'' which debuted in 1994 and launched the careers of George Clooney, who left the show in 1999, and others in the ensemble cast.
Like many ''ER'' fans, Edwards hopes for the return of Clooney's character, Dr. Doug Ross. He has said Clooney would be a fool not to make a cameo.
Said Edwards: ''I would never judge anybody else. All I can do is share that I had a good experience, and I hope that whoever gets asked and has the opportunity does do it.''