'Grey's Anatomy': Derek takes out an inoperable tumor; Lexie wears a diaper

Tonight's "Grey's Anatomy" was all about finding your peace -- or making it -- however you can. In this case it involved Derek doing the impossible surgery in the OR and Lexie wearing a diaper in surgery.

Yes, I know how that sounds.

Derek does the voiceover in this ep, which was very well directed by Chandra Wilson (Woot! Go Bailey! If she can sing and dance too, I'll just lose it) and opens by talking about what drew him to surgery: the quiet, and the shutting out of everything else in the world while it's going on. He's studying some scans when Isaac, a tech, come in and shows him an amazing MRI of a giant, very dangerous tumor on his spine. Isaac's the patient, and he talks Derek into taking on his surgery -- which is really the operation of a lifetime, if he can pull it off.

And don't all of the other surgeons know it. One by one, Cristina, Mark, Callie, Lexie, Hunt, and Arizona all come in, practically drooling (though still worried about Isaac) while Derek's trying to figure out whether to take the case. Even Bailey's blown away, calling the tumor dangerous, complicated, smart and beautiful -- the reason she got into medicine. But the Chief won't go near it -- it's just too dangerous, and they might need to cut the spinal cord to get it all out. Even after Derek tells him that the patient is an employee, the Chief says the hospital's not a charity, and they don't have the pro bono budget to cover higher surgeries for every employee. "What happened to you?" Derek asks him. There was a time when he would've encouraged Derek to take the risk and now he walks away. In the end, Derek defies the chief and his new computer-generated schedule and books the surgery -- even though he's apprehensive, it's just too good a case not to. He's gone rogue.

First there's a contest among the residents to see who's got the skills to handle microsurgery, and a cocky Cristina totally whiffs. Avery gets to scrub in. So does Lexie, who'll keep an eye on Derek because this is one bear of a long operation. Of course, those two get all macho and Avery brags about how he never has to take breaks -- so Lexie decides to wear a diaper so she can stay in surgery for longer. She's totally embarrassed by it until Cristina finds out and gives her a hilarious "atta girl -- this means you're hard-core" speech.

Before he goes under, Isaac tells Derek that he needs to be inspired in this surgery -- and if need be, he should cut the spinal cord. Isaac tells Derek he's survived war, the death of all of his family, and the loss of his country -- and he'll survive the loss of his legs if he has to. There's always a way -- even when things look like there's no way, there's always a way, he says. It's an amazing speech, and not for the last time this episode do I look with awe at Isaac.  

But it doesn't go well -- Derek gets in there and finds that the tumor is much more involved than it looked on the scan -- and he stands there for 10 hours trying to come up with a plan to attack the thing, before the Chief comes in and boots him out. He later explains to Isaac that it was just too risky, and since he still has use of his legs he couldn't bear to cut the cord. He'll do better tomorrow, Isaac tells him.

So Derek goes home and talks it through with Meredith -- and comes up with a strategy. He's gone all zen, and now he knows he needs to just go in and cut. Avery engages in a little chest-thumping with Lexie and ribs her about her diaper, and Lexie's response is just too good not to include in its entirety.

"I wore a diaper yesterday, yes -- and I will wear one today. If it helps Dr. Shepherd get through the surgery, I will wear a diaper. My diaper is awesome. My diaper is hard-core. You wish you had the balls to wear my diaper. I'm gonna wear it, and I'm gonna wear it with pride. And if I have to pee in it? Oh, I'll pee. Because I am a surgeon. This is America. And I will do what needs to be done. So you can kiss my hard-core, diaper wearing ass."

Doesn't make me want to go out and get a case of Huggies, but Chyler Leigh delivers it absolutely brilliantly. Back in surgery, which they're doing because Derek talked the chief into believing he's going to cut Isaac's spinal cord, the attendings come in and keep Derek company over the course of the 26-hour (you read that right) operation. Things are momentarily distracted when a tense, dehydrated Derek throws up, but the real trick is when he's down to the last set of blood vessels that connects the tumor to the spine, and he has to pick the one to cut. The wrong decision could kill the patient.

In the end, the surgery is successful -- Derek not only saves Isaac, but also doesn't paralyze him. When he wakes up, Isaac's convinced that the surgery didn't go well, because he can move his feet -- but he's so thrilled, and it's a relief that there's a straight-up happy ending without a disaster thrown in. That is, until Derek runs into the chief, who all of the attendings have blocked from his OR during Isaac's surgery (Arizona putting her foot down and says she won't allow him to go in and be a bully on her watch -- go Arizona!).

We can't keep fighting, Derek tells him -- let's try to put this behind us and move on. And then the Chief fires him. Right. Because he's going to axe the world-class neurosurgeon who just pulled off a once-in-a-lifetime surgery that could definitely raise the hospital's ranking just because he's pissed. Chief, the fact that Derek calls you out on your stuff makes him the best friend you have right now. And Derek adopts a little bit of Isaac's Zen by telling the chief to sleep on it, and they'll talk tomorrow. Nice!

Also...

• Izzie doesn't show up for her treatment appointment, which is really bad, and through his anger Alex is heartbroken. Reed gets the best line of this storyline, though, telling him: "[Your] being ditched by Cancer Wife hasn't changed my mind -- you're still a douche."
• There's a fantastic small moment between Owen and Cristina, where he helps her with her microsurgery skills. He knows she's been dying to get into surgery and really bummed that she screwed up and got shut out of this one. Also, Cristina explaining why she wants to be in a surgery so long she needs to wear a diaper is priceless -- as is her decision to wear one.

What did you think? Did you doubt that Derek would succeed with Isaac's surgery? How will the Chief keep Derek around after sleeping on it and still save face? How dumb was Izzy to skip her appointment?

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