Below are some sneak previews from this week's episode of Grey's Anatomy, "Tainted Obligation." In the first, Alex receives a wake up call from a bear (and we're not talking about Cristina's Mr. Bear toy here). He then decides he wants to move back to Mer's.

Izzie's not up for that, though, because she just can't move backwards ...

[video url="http://www.tvfanatic.com/videos/tainted-obligation-sneak-preview-1/" title="Tainted Obligation Sneak Preview #1"] [/video]

Follow the jump for two more clips from the episode, in which Izzie treats a patient suffering from cancer and waiting for the right moment to propose to his girlfriend of eight years.

Also, Mer and Lexie's father, Thatcher, arrives at SGH in terrible shape ...

[video url="http://www.tvfanatic.com/videos/tainted-obligation-sneak-preview-2/" title="Tainted Obligation Sneak Preview #2"] [/video]

[video url="http://www.tvfanatic.com/videos/tainted-obligation-sneak-preview-3/" title="Tainted Obligation Sneak Preview #3"] [/video]

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