This episode was a different as the usually make the season premiers. The unique idea to show the action and day of ER staff from four angles - I liked it. And very create name for that kind of episode.
I most say, most of those four stories I enjoyed Carter's. His family and that spectacle his life looks - it is somehow different and out of the usual stuff they deal and Carter's character is that kind complicate and there is always some improvement and development for his story with that kind of storylines.
Also Mark's storyline was fascinating as he now has to deal with the aftermaths of his actions and it is not easy for him. But it almost looks like for Elizabeth the truth is out but she does not dear to accept that. And I understand why as she once was a very similar situation.
Benton's storyline - it was somehow refreshing and finishing up about what happened with his sister but nothing too special. Benton has always somehow been... he has had interesting storylines but..
And Weaver's one - it was the first but it was weaker than others.