Grey's Anatomy Grey's Anatomy

Cat's out of the bag! And Meredith (Ellen Pompeo) is going to try her damndest to shove it back in and pretend it never escaped in the first place.

On Thursday's Grey's Anatomy, Maggie (Kelly McCreary) finally worked up the courage to tell Meredith that they're sisters. And it did not go over well. But a lot of other stuff happened before that.

In the opening montage, we learn that Maggie runs, talks to her parents on the phone a lot, and once solved a Friday New York Times crossword puzzle in 11 minutes when she was 13. Oh, and she is done trying to win Meredith's favor.

"You can't keep avoiding her," Richard (James Pickens Jr.) tells her, WHILE HOLDING A NEW YORK TIMES CROSSWORD PUZZLE. Bio-Dad Alert!

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Throughout the episode, Miracle Maggie runs circles around the other doctors, proving that she is practically superhuman when it comes to her job. But she also makes some blunders too. I love that she can't remember Jo's (Camilla Luddington) name. Welcome to Trying to Keep Up with the Interns on Grey's, Maggie!

Among the patients today are a pregnant woman who's at great risk of dying during childbirth but has decided to go ahead and have the baby, and an 88-year-old woman with cancer who wants to die, but whose daughter won't let her sign a DNR. We get a pair of West Wing shout-outs as Maggie and Jo walk-and-talk through the hospital and Maggie asks, "What's next?" Heh.

Jo gets off to a rough start with Maggie by first trying to convince the cancer woman's daughter to let her mother die in peace, and then not telling Maggie that Alex (Justin Chambers) is her boyfriend — leading to Alex having to awkwardly admit to Dr. Lebackes (Patrick Fabian) in the OR that he might be leaving. Maggie gets so exasperated that she kicks Dr. Willis Jo off her service, but not before briefly donning her mentor hat and advising Jo to "bring the thunder" because she's young and pretty and might have a tough time being taken seriously.

Grey's newcomer Kelly McCreary: Maggie and Meredith are like "oil and water"

Also not thrilled with the new doc is Owen (Kevin McKidd), who yells at Maggie for digging into the records of the transplant patient Cristina was treating the day she left. "Do you really think you could find something that she didn't?" Owen asks. Looks like someone is still smarting over Cristina's departure.

In the cafeteria, Maggie runs into Meredith and Derek (Patrick Dempsey) having a family lunch, and her anti-Meredith resolve softens a bit with the knowledge that Meredith adopted a needy African orphan. "Isn't it funny, she adopts a kid, her mother gives one up?" she later says to Richard. OUCH! I'm going to have multiple bruises from being beaten over the head with an irony hammer by the Grey's Anatomy writing team.

Meanwhile, Amy (Caterina Scorsone) is enthusiastically trying to AA-bond with Richard, who's not having it, and introduces herself to Maggie as Derek's sister. "I'm sorry, is everyone in this room somehow related?" she responds. Oh, Maggie. Little do you know. After Amy leaves, Maggie grills Richard about Ellis. Richard says he doesn't know anything about the details of Ellis giving Maggie up for adoption (sad), but before he can answer her question about how close he and Ellis were, Jo interrupts them with news that the pregnant woman is not doing well and needs an emergency C-section. Maggie goes into hero mode again, saving both the woman's life and the baby's. She also walks in on Callie (Sara Ramirez) and Arizona (Jessica Capshaw) fighting about Arizona taking the Geena Davis Fellowship.

Next up is a case of a woman who had a stroke after having sex with a guy she met at the gym. Check out the look on Amy's face when Maggie, Amy's new BFF, calls Derek "the other Dr. Shepherd":

Later, Amy gives a pun-filled speech about how she kind of wants to have stroke-inducing sex, and she and Maggie high-five over their shared horniness. Amy is my new favorite. She also tells Maggie what a great sister Meredith is. There's that hammer again. (Side note: I LOL'd at stroke-sex guy saying he wanted to stick around to ask the girl out because she was cool "before she went all derp.")

Maggie has another foot-in-mouth moment when she meets Jackson (Jesse Williams) and immediately gets on his bad side by saying that putting an end to Bailey's genome project makes the board look like a "bunch of morons." Oy. At least Bailey likes her.

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There's another Maggie/Meredith showdown when Meredith tries to intervene in the cancer patient's case. Then, at the most inopportune moment, Maggie gets a singing telegram from her parents, involving a ukulele-wielding man in a sturgeon costume serenading her about what a great surgeon she is. Maggie's mortified, but calls her folks to thank them and confesses that she may have made a mistake coming all the way to Seattle.

Things start to look up for Maggie when, thanks to Bailey's project, she finally has an answer for Cristina's patient's family, absolving them and Cristina from any responsibility about their child's death. Owen is impressed. Then, the cancer woman crashes and Maggie swats Meredith away, exerting a halfhearted attempt to restart the patient's heart before calling time of death. Meredith immediately tattles to Owen, but after hearing Maggie's explanation of the patient's wishes, she comes to her defense as they break the sad news to the woman's daughter.

Arizona, so inspired by the pregnant lady's selflessness, says she's willing to give up the fellowship so she and Callie can have another baby. Callie tells her she shouldn't. Callie and Arizona are the new Meredith and Derek.

At the end of the day, Jo brings her thunder and insists that Maggie keep her on her service. And Maggie, feeling like a million bucks, decides to get the conversation with Meredith over. "My mother was Ellis Grey," she blurts out, as Meredith's trying to walk out the door. Meredith asks what she's after and tells Maggie she's either misinformed or lying. Yikes.  

Maggie's hope:

Maggie's reality:

I have to say, I'm glad the show didn't drag out the will-she-or-won't-she tension between Maggie and Meredith, and now I guess it's only a matter of time before Richard's secret is exposed as well.

What did you think of the Maggie-centric episode? Were you surprised by Meredith's reaction to her news? Do you hope she sticks around for the rest of the season? Sound off in the comments!

Grey's Anatomy airs Thursdays at 8/7c on ABC.