I don't know when the season finale is, but according to TV Guide, Greene's end is near. See spoiler below for the episode listing. ER May 9 On the Beach 60 min. Anthony Edwards, who has been a mainstay of ER since its premiere in 1994, plays Dr. Mark Greene for the last time. In the affecting episode (written and directed by executive producer John Wells), Mark is in Hawaii after leaving County General to enjoy what little time he has left. With him is his daughter Rachel (Hallee Hirsh), and Mark hopes the trip will give the often antagonistic pair a chance to reconnect and heal some old wounds before it's too late. Then the unexpected arrival of Corday (Alex Kingston) and baby Ella allows the weakening Mark to see his fractured family reunited. Jen: Christine Harnos. Cleo: Michael Michele. Benton: Eriq LaSalle. He's had some goofy storylines over the years, but I'll be sad to see him go. Wish they could have found another way to write him out of the show.