What the...? It may be Friday, but we're still sitting here on the couch, staring at the television set with mouths agape. Where the hell did this episode come from? It had more OMG moments than the entire fourth season combined! This episode was entitled "Migration," and though Meredith (Ellen Pompeo), Alex (Justin Chambers), Cristina (Sandra Oh), and Jackson (Jesse Williams) didn't sprout wings and fly south in a V-formation, they might as well have since they're all contemplating leaving Seattle. Or maybe wings would help them stay airborne... but more on that later!

First of all, the job offers are rolling in — for everyone except April (Sarah Drew), that is. Owen (Kevin McKidd) and the other attendings are all sweating, thinking that if all the residents jump ship, so too will Seattle Grace's prestige. For example, Karev of all people gets an unpredictable offer from Johns Hopkins. Cristina, meanwhile, has programs practically falling over themselves to hire her. Jackson is being wooed by UCLA. And Mer is still being pursued by Boston. April, on the other hand, has all of her offers rescinded after her crash-and-burn at the boards. Even Owen tells her that she's no longer a candidate for a job at Seattle Grace. (Burn!)

This episode's patients-of-the-week are familiar faces to us TV fans: Chloe from 24 (Mary Lynn Rajskub) and Jimmy Barrett from Mad Men (Patrick Fischler). But in this show, they play a thrice-married couple who bring back an intestinal worm from bad sushi they ate in Thailand.

But the real news is what happens with Bailey (Chandra Wilson)! The case of the intestine-eating worm lures her to the hospital, to the consternation of Ben, who wanted to stay home with her to relax and do the crossword. He is such a grump about it that Bailey puts down her scalpel mid-operation and starts doing the crossword right in the OR. When she asks the fellow surgeons what one of the answers might be, a 13-letter response to the clue "My question to you," Ben corrects her by saying that it's actually 14 letters. And he should know, because the answer is "Will you marry me?," and he knew that because he designed the puzzle and submitted it to the newspaper. OMG!

It's so ridiculously romantic, we can hardly stand it, So later, at home, Bailey undresses to a thong and tells Ben to propose to her again. But this time, he says that he just found out that he was accepted into UCLA's surgical intern program. Dang it, why can't Bailey have her happy ending? And FYI, the couple with the worms ended up just fine.

Arizona's (Jessica Capshaw) friend Nick isn't so lucky. First of all, Arizona is giving him the cold shoulder, making him think that he should just go to Belize for the rest of his days instead of dying alone in Seattle. When Teddy (Kim Raver) and Cristina open him up, they see that the tumor has taken over his heart. Arizona breaks the news to Nick once he wakes up, and he is for once seriously remorseful for not seeking help sooner. It wrecks Arizona, and she takes out her frustration on Alex, who decides to take Hopkins's offer, telling him that he can't go with the rest of the crew one their mission to Boise to pick up conjoined twins.

Derek (Patrick Dempsey) shows Meredith their completed house, and it's appropriately dreamy, but he says that it isn't his dream anymore. Now he wants to move to Boston with Meredith. She resists, mainly because she thinks that if she stays in Seattle and Cristina goes to Stanford, they'll be able to see each other often. But finally she relents and tells Owen that she's East-Coast-bound.

Owen, meanwhile, is still getting mixed signals from Cristina. Teddy can't figure out why Cristina's so adamant about leaving Seattle, and Owen finally tells her about his crime. Meredith, who's always known the truth, tells Cristina that she doesn't need Owen — but Cristina tells Mer that she's no longer her "person;" Owen is. (OMG!) At one point, Cristina comes home and cuddles with Owen, and then later, she sexes him up in the on-call room. But right afterwards, Cristina breaks the news: "I'm leaving." (OMG!) She decides to go to the Mayo Clinic.

Also, Mark (Eric Dane) is awkward around Lexie (Chyler Leigh) since she confessed her love, and April is drinking herself into a stupor and refusing Jackson's pity.

But the real shock happens at the episode, to the strains of Feist. All of a sudden, we see the wreckage of the plane taking the docs to Boise strewn in a forest. And we know that at least Meredith, Cristina, Derek, Mark, Lexie, and Arizona were all onboard. So the rumors were true! It's gonna be one vicious season finale, folks. See you there.

Catch the season finale of Grey’s Anatomy on Thursday, May 17 at 9 p.m. ET/PT on ABC.

Dan is a contributing writer at Wetpaint Entertainment. Follow him on Twitter @SixFourDan.

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