The passing of the torch from Mark Greene to Carter is finally complete. Korday sends the ER a letter that Mark wrote as a beautiful farewell letter to all of his co-workers, and concludes it with the news that Mark passed away. As expected, the news hits the main characters in different ways: Weaver is almost incapacitated by the news, she has a hard time dealing with it because he stood up to her, while remaining as pragmatic and honorable as possible and doing his job. Susan cries anytime she has nothing to do or when she sits down. Carter is aware of what Mark meant to the ER and to him in how he developed Carter into the ER physician he is today, but Carter is shell-shocked, and can't make decisions fast enough to save a man whose airway is obstructed and Romano has to save the day with a clever tracheotomy. Romano is reflective of how the body can turn on itself in the form of cancer as he removes malignant growth in a girl (found only due to her being injured) that was hit by accident along with her father. Most of the ER staff show up for a get together in Mark's honor at a bar in which they celebrated Mark's birthday in the past. Abby is drinking a huge margarita-like drink, gets buzzed, and Carter shows up and finds her, and wants to take her to an AA meeting. She bites his arm when he picks her up and puts her on his shoulder. They, instead, have coffee. Abby promises to go to an AA meeting that day. Carter, pulling an all-nighter with sobering up Abby, has to be back at the ER early in the morning, and he and Pratt deal with Mark's diabetic, multi-medical problem patient. Finally that patient mistakes Carter for Mark (his eyesight must have gone bad on him with his diabetic condition), and Carter stays with the patient until he passes away (Carter dozes off to sleep). Weaver interrupts Susan and Carter in the doctor's lounge while he is offering comfort to Susan. Weaver then starts to clean out Mark's locker, but can't bear to finish the job, and asks Carter to finish up, and he obliges. Weaver tells Carter that the rest of the ER will be looking to him to be the man in charge, to fill Mark's shoes. During the clean-up, the equivalent of passing the ER torch to Carter is done when Carter sees Mark's stethescope, and takes it as his own now. It was a nice scene. Abby tells Carter that she did go to an AA meeting that day, and that she did it for him. Later, in a case where some guy almost shoots off his face, Gallant has problems with the severity of the injuries and almost throws up. Carter tells Gallant to go get some air. Later history repeats itself when Carter goes to see Gallant outside and tells him that there are 2 kinds of doctors, those who shut down their feelings, and those who don't. No shame in being a doctor with feelings, and offers encouragement to Gallant. Mark did this with Carter 8 years ago when Carter was still a med student in the ER. Again, Carter is stepping up and carrying on the mantle to fill Mark's shoes. Oh, Pratt's stuck at County General because he got his 3rd choice for hospitals to work at for his residency.