Good ol’ Dr. Mark Greene. One of the best characters ever on ER, he died of a brain tumor towards the end of the 2001-02 season, and the goodbye was one of the most gut-wrenching, tearful moments in the series.
Just re-watching his final scene in the video at the bottom of this article brought all the sadness back.
The one scene, besides his death, that I remember most, was when Susan left for Arizona and Dr. Greene watched her disappear forever on the train.
