Tonight, Grey's Anatomy finally returns from its hiatus with a new episode, "I Will Follow You Into the Dark." From what we've seen so far, there's a lot going on at Seattle Grace.

Izzie Stevens' ailment will be revealed at last, and whatever it is, the next step will be interesting. Derek decides he's had enough people die on his watch and walks off the job.

Callie's still stressing over Arizona (with Mark along for comic relief, of course), and Adele returns to settle issues between Bailey and the Chief. Sounds like a good one tonight!

Check out our video and photo sections for more previews! As always, you can discuss "I Will Follow You Into the Dark" before, during and after the episode in our

Steve Marsi is the Managing Editor of TV Fanatic. Follow him on Google+ or email him here.