At first, little was known about Dr. Mark Sloan, the new McSteamy doctor on Grey's Anatomy, but that doesn't mean he wasn't noteworthy.
In fact, his being shrouded in mystery for much of the series only increases his appeal. That, and he's McSteamy. He's the man, revealed in Season Two, who was the catalyst in Derek and Addison's divorce. It was upon walking in on Mark and Addison in bed together that Derek fled New York for Seattle.
There, the neurosurgeon began a romance with an intern named Meredith, and the rest is history. Well, sort of.
When Addison eventually came out to Seattle, Derek took her back and they tried to reconcile. So when Dr. Mark Sloan appeared one day, he was not well received... by Derek's fist. He sutured his own face after being cut.
Mark's purpose was to take Addison back to New York, as he is very much in love with her. A plastic surgeon, he ended up assisting on a rare operation during his brief stay and giving career advice to Alex.
Despite his best efforts, though, Addison did not follow Mark back to New York. But in the second episode of the third season, he appeared wearing nothing but a towel in Addison's hotel room, after receiving a transcontinental booty call.
Mrs. Dr. Shepherd had just learned of her husband's affair with Meredith and embarked on a serious bender - one that ended with Mark back in the Emerald City. It was perhaps the most talked about moment of the season, and despite the fact that Addison didn't want to date him seriously, Sloan stayed in Seattle.
As a full-time plastic surgeon on Seattle Grace's staff, Mark tried to woo Addison, slept with Callie, hit on Meredith, terrorized Alex, and did all the other things that insecure, self-destructive Mark does. He even made a bid for Chief of Surgery. Still, relatively little is known about him and we look forward to seeing this hot character evolve.
MEREDITH: "McSteamy! Woo hoo!"
MARK: "McSteamy? That's what you're calling me now?"
MEREDITH: "Yes... but I don't think you are supposed to know that."
MARK: "How's my favorite dirty mistress?"
MEREDITH: "No, now I'm an adulterous whore!"
Lexie: [narrating] Grief may be a thing we all have in common, but it looks different on everyone.
Mark: It isn't just death we have to grieve. It's life. It's loss. It's change.
Alex: And when we wonder why it has to suck so much sometimes, has to hurt so bad. The thing we gotta try to remember is that it can turn on a dime.
Izzie: That's how you stay alive. When it hurts so much you can't breathe, that's how you survive.
Derek: By remembering that one day, somehow, impossibly, you won't feel this way. It won't hurt this much.
Bailey: Grief comes in its own time for everyone, in its own way.
Owen: So the best we can do, the best anyone can do, is try for honesty.
Meredith: The really crappy thing, the very worst part of grief is that you can't control it.
Arizona: The best we can do is try to let ourselves feel it when it comes.
Callie: And let it go when we can.
Meredith: The very worst part is that the minute you think you're past it, it starts all over again.
Cristina: And always, every time, it takes your breath away.
Meredith: There are five stages of grief. They look different on all of us, but there are always five.