Will Derek and Mark rekindle their old friendship?

Karev finally gets to scrub in!

Sorry, Mark, Meredith's having none of it.

But Addison has eyes on someone else... and a different life entirely.

Mark makes a pass at Meredith... to no avail.

Cristina, Mark and Meredith look on.

(after Meredith shoots down his offer of revenge sex)

Mark in his usual rouge glory.

Please, Mark asks?

Mark Sloan won't be Chief, but he made the rest of the candidates vying for it work harder.

The Season Four cast of Grey's Anatomy: Starring the lovely Ellen Pompeo (Meredith Grey), Patrick Dempsey (Derek Shepherd), Sandra Oh (Cristina Yang), Katherine Heigl (Izzie Stevens), T.R. Knight (George O’Malley), Justin Chambers (Alex Karev), Chandra Wilson (Miranda Bailey), James Pickens, Jr. (Richard Webber), Sara Ramirez (Callie Torres), Eric Dane (Mark Sloan) and Chyler Leigh (Lexie Grey).

In what appears to be his final act, Nathan convinces Peter to turn on Adam. After all, he's not a nice guy.