It's official. McDreamy has channeled his inner Sarah Palin and gone rogue.

In the below sneak previews of this week's episode of Grey's Anatomy, "Give Peace a Chance," Dr. Derek Shepherd learns that a hospital employee has a spinal tumor.

He wants to do what he can to help, despite seemingly long-shot odds. Richard tells him no. McDreamy doesn't care and begins assembling a surgical team anyway.

Like we said, he's gone rogue, people, and there's no going back.

Here's the first clip from the episode, which also features Derek narrating for the first time, and marks the directorial debut of Chandra Wilson (Dr. Miranda Bailey):

[video url="http://www.greysanatomyinsider.com/videos/give-peace-a-chance-sneak-preview-1/" title="Give Peace A Chance Sneak Preview #1"] [/video]

Follow the jump for four more sneak previews from the episode, which is believed to revolve entirely around this story line (at least it's looking like a good one) ...

[video url="http://www.greysanatomyinsider.com/videos/give-peace-a-chance-sneak-preview-2/" title="Give Peace A Chance Sneak Preview #2"] [/video]

[video url="http://www.greysanatomyinsider.com/videos/give-peace-a-chance-sneak-preview-3/" title="Give Peace A Chance Sneak Preview #3"] [/video]

[video url="http://www.greysanatomyinsider.com/videos/give-peace-a-chance-sneak-preview-4/" title="Give Peace A Chance Sneak Preview #4"] [/video]

[video url="http://www.greysanatomyinsider.com/videos/give-peace-a-chance-sneak-preview-5/" title="Give Peace A Chance Sneak Preview #5"] [/video]

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