Credit: Randy Holmes/ABC Television Group © 2012 Disney Photo: Mark and Jackson Care For a Patient on Grey's Anatomy Season 8, Episode 15

Okay, so we have another so-called "crossover event." But we think the word "event" implies a little too much excitement because, honestly, we've seen it all before. Take one VIP patient — usually a family member of a doctor — take that VIP patient from Seattle to LA or vice versa along with a handful of doctors, save that patient's life, send everyone back where they belong. Same old, same old. One notable exception: Addison didn’t get a chance to raise some hell at Seattle Grace-Mercy West.

So here's the situation: Erica, the mother of Cooper's kid Mason, has a tumor in her brain. And if you don't know Cooper, you've obviously been turning off your television sets at 10 every Thursday night, and for that we shame you. Amelia Shepherd wants to bring Erica to Seattle Grace to get her brother Derek (Patrick Dempsey) to help remove the infiltrator. Brother and sister conclude that they have only 90 seconds to interrupt the blood flow and do their thang. (90 seconds? That's longer than most Kardashian weddings.) Derek is a total naysayer, saying that it's too difficult a procedure, especially for his recovering addict of a sister to take on.

Lexie (Chyler Leigh) keeps on being Amelia's cheerleader and even comes up with the silver-bullet idea: going through the carotid artery instead of the femoral. With that game plan, even Derek has to admit that they have a fighting chance. They call Erica up to Seattle, and with her comes Cooper, Charlotte, and Mason. Erica tells Mason that she's very sick and might be dying tomorrow. (This is why procrastination is bad, folks.) She goes into surgery, and Derek and Amelia rock it out in only 85 seconds. Of course, more obligatory complications spring up, but the short story is that Erica survived and even mustered the energy to wave to Mason through the window. And in more happy news, Charlotte finally admits that she loves Mason.

Richard (James Pickens Jr.) appears like the ghost of Jacob Marley and tells Ebeneezer Torres (Sara Ramirez) that she should bestow her top-secret studying method on Meredith (Ellen Pompeo). (The residents are all gearing up for their oral board exams.) Callie is skeptical but reluctantly agrees. She recruits Mer for her current case, which is a doozy (and not for the faint of stomach): a deli worker got his hand stuck in a meat grinder, which means we got lots of loving close-ups of a pulverized hand.

Credit: Randy Holmes/ABC Television Group © 2012 Disney Photo: Derek on Grey's Anatomy Season 8, Episode 15

Callie has Mer make the tough calls, and Meredith decides to try to save the hand instead of amputating it. They even use one of the guy's toes to replace his thumb. When we sign off, the guy's appendage actually resembles a hand. And Mer and Callie actually bond, since they're both happily married moms now and have no reason not to be friends. Callie tells Mer to report to work every day at 4am so that they can study. (Those kinds of hours are why we'll stay bloggers and not become doctors.)

Meanwhile, one of Bailey's (Chandra Wilson) old patients goes to Mark (Eric Dane) and Jackson (Jesse Williams) requesting a lymph node transfer to correct her lymphedema because her arm is seriously swollen. Like, it's the size of Texas... and almost as big as Mark's ego. Bailey had initially denied the woman the surgery, thinking that she was too extensively scarred from her barrage of surgeries. When Mark and Jackson proceed anyway, Bailey micromanages the operation to the point where, at Mark's encouragement, Jackson kicks Bailey out of the OR.

Also, Alex's (Justin Chambers) intern Megan collapses, and he realizes that a) her name is actually Morgan, and b) she's pregnant. She has an aortic dissection, which means that she needs bypass surgery, which means that Arizona (Jessica Capshaw) has to deliver her baby prematurely. Mother and baby both emerge from the OR in good condition. The whole ordeal makes Alex realize that he should probably be a better person, but Arizona consoles him, telling him that he reminds her of herself.

Cristina (Sandra Oh) and Owen (Kevin McKidd) are out of scrubs the whole episode because they spend the entire time in couples counseling. And it could not be going worse. They're acknowledging and addressing each other, which is a start, but they're also screaming at each other. Owen just can't wrap his brain around the fact that some people just don't want kids. Cristina just wants him to be her "person". By the end of it, they seem further apart than ever. Where's the steam vent when you need it?

Credit: Randy Holmes/ABC Television Group © 2012 Disney Photo: Amelia on Grey's Anatomy Season 8, Episode 15

In Los Angeles, in that most private of practices, the big dilemma is that Jake did in vitro fertilization on a woman, not realizing that she had a donor heart. The woman suffers congestive heart failure. Addison, Jake, and Sam race to save both mother and child, but only the little one survives.

Sam has even more on his plate, though, because Sheldon deduces that his recently-returned sister Corinne's positive outlook is a result of hypomania (a type of bipolar disorder) and that she still needs a lot of help. Corinne accidentally reveals that she's been in LA for five years, which makes Sam go apoplectic because he and his mother spent all that time being worried sick about her. But Corinne says that he has no idea how hard her life was, since she was doing so many destructive things as a result of a disorder she didn't realize she had.

Also, hot paramedic Scott wants to be a part of Violet's life — at least, a bigger part than just resident-boytoy. But Violet tells him that she only wants him for sex. Kinda impersonal, but we gotta respect her forthrightness. Meanwhile, she and Pete are actually sorta re-bonding as platonic pals again. And speaking of improved relations, Jake finds Addison and asks if their attraction to one another ever became more than sexual, and Addie says yes! But our question is this: can we call him McBratty?

Catch an all-new Grey’s Anatomy on Thursday, February 23 at 9pm ET/PT on ABC.

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