History is full of perfect pairings: peanut butter and jelly, a hot bath and a good book, Sonny and Cher. But can a pairing, no matter how perfect, sometimes fall into a rut? Dr. Richard Webber (James Pickens Jr.) seemed to think so, and on the Thursday, March 17, episode of Grey's Anatomy, he kicked things off by hosting an impromptu "resident scramble," which reassigned the residents and attendings. 

New pairs included Jo (Camilla Anne Luddington) with Meredith (Ellen Pompeo), Amelia (Caterina Scorsone) with Penny (Samantha Sloyan), Ben (Jason George) and Andrew (Giacomo Gianniotti) with Arizona (Jessica Capshaw), and Stephanie (Jerrika Hinton) with a bunch of puppies in pediatrics (who were there to help raise patients' spirits for the day). Needless to say, no one was excited about this idea except Webber — though the new matchups did give Jo the opportunity to tell off Meredith.

Jo's Claws Come Out

It goes without saying that Jo and Meredith were not exactly a perfect couple. Mer's jabs continued until she finally told Jo flatly, "You're just not Blake." It turned out that was the straw that broke the camel's back, and rather than slink back into the shadows, Jo came out fighting.

"I'm a surgeon. I'm a human being. I'm not some stupid lump that you can just kick around or talk down to or talk down about or dismiss and discount! I get it. You don't like me. I'm here. I'm in Alex's life, and I'm staying, and you have to start respecting that," she said.

In response, Mer shrugged and mumbled, "I don't know where you're getting this." (Really, Meredith?)

"I am trying to move forward, but I can't because you're always around the corner blocking my way, making everything so damn hard!" Jo continued, prompting Meredith to argue she was overreacting. "No, I'm not! That's exactly what I'm talking about. I'm done. I'm done with all of it. You know, call your damn Army guy back, and get your boyfriend!"

Arizona Rolls the Dice … and Wins

Meanwhile, Arizona had her hands full tending to Courtney (Casey Wilson), an accountant 23 weeks pregnant with quadruplets. When Ben did an ultrasound on the expectant mom, however, he could only find three babies — because the fourth had moved down, signaling that Courtney was actually in labor (not good this early on). Against common practice, Arizona made a judgment call and opted to deliver the single baby while trying to keep the others inside their mom. Though her decision raised some eyebrows, ultimately everyone got on board for the risky move.

As Arizona went to work, Ben distracted Courtney with questions about his taxes, since there had been a lot of discussion about the most strategic way for he and Miranda (Chandra Wilson) to file now that she was earning so much more than him. Happily, Arizona's gamble paid off, and all four babies survived. Even Alex (Justin Chambers) marveled at the result. "No one else could have done what you did," he said.

Meredith Tries to Ghost Dr. Thorpe

After giving an update on their military patient (who was doing fine, thankfully), Callie (Sara Ramirez) not-so-casually mentioned that Dr. Thorpe was starting to wonder if Meredith had given him a wrong number. Apparently, he'd called her — several times — and she hadn't responded.

Meredith explained that if she answered, he would ask her out, and she would have to say no, and then she wouldn’t know when to hang up, so she'd decided to save them both the trouble and simply not answer. (Insert eye roll here.)

Despite her best attempts to thwart his advances, however, Mer eventually broke down. Sitting on a bench outside of the hospital, she pulled out her phone and was just about to text him when she realized he was sitting on a bench a few feet away, which could have been creepy if he weren't so hot.

"I can see right about now you're thinking I'm some kind of stalker," he began. "Yeah, I've called, and I've texted because I wanted to see you again, and I thought I'd ask you out, but I can't do that if you don't call me back." Meredith didn't say anything, but she did stand up, so that was progress.

"I thought I'd show up here and ask you. That way if you were going to turn me down, you'd have to do it in person," he said with a smile. (Obviously, no one is going to say no to that smile.) "So what do you say, Dr. Grey? Would you like to go out with me?"

April Gets Outed

In other relationship news, April (Sarah Drew), now 12 weeks pregnant, seemed nowhere nearer telling Jackson (Jesse Williams) that he was going to be a father again. Arizona and Alex decided to intervene and try to talk some sense into April — but their pleas fell on deaf ears.

"I'm worried that you're doing this alone when you don't have to," Arizona reasoned to April. In turn, April informed Arizona that not only was she not ready to tell Jackson, but she had also decided not to perform any fetal testing on her baby.

"You need to tell Jackson, and you need to let me give you a full workup," Arizona firmly replied. "I can feel the boulder starting to roll, and I am trying to stop it." When that didn't work, she tried another angle, adding, "I am trying to help you get what you want, which is a healthy baby — one that's not going to go through horrible pain." That didn't work either.

Later, Alex cornered April and warned her, "The longer you wait, the worse it's going to be." April disagreed.

"I'm not telling him because we have been through enough, especially him, because he never got over the last one. He never had a chance to, and I am hanging on to every last shred of faith I have that this time it will be OK, but he doesn't have that, so it will just be better if he doesn't know yet," she explained.

"It won't. You're making it worse," Alex snapped.

But while April seemed unmoved by these protests, as the episode drew to a close, she was headed to talk to Jackson (presumably to tell him their news). The only problem? Arizona had beaten her to it. April pushed the door open to find Jackson and April having what appeared to be an intense conversation.

"Why is she telling me this?" he asked. Uh-oh.

Tell Us: Was Arizona right to tell Jackson about April's pregnancy?

Grey's Anatomy airs on ABC on Thursdays at 8 p.m. ET. 

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