Whether she's imagining stuff, hallucinating due to a brain tumor, or he's real, we have no absolutely idea. But Dr. Izzie Stevens is definitely getting her world rocked by Denny in this clip from tonight's episode of Grey's Anatomy, "In the Midnight Hour."

Her boyfriend, Dr. Alex Karev, stands outside the room listening in a state of confusion. We would be as well if a ghost was ransacking our significant other.

Enjoy the clip below, then follow this link for three more videos as well as additional Grey's Anatomy spoilers and rumors pertaining to tonight's show ...

[video url="/videos/hallway-awkwardness-on-greys-anatomy/" title="Hallway Awkwardness on Grey's Anatomy"] [/video]

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