For tonight's 300th episode, Grey's Anatomy decided to tug at all the heartstrings with some throwback nostalgia only the series' most sentimental fans could appreciate. From the original soundtrack trickling back into the fold to our newest crop of interns — including Glasses! — becoming a commiserative, sleep-deprived little family right there on the hideaway hall beds to the return of some strangely familiar faces, it's an Easter egg extravaganza at Grey-Sloan Memorial Hospital tonight.

Of course, this episode shouldn't be centrally located at the hospital at all, since it's time for the Harper Avery awards, and our own Meredith Grey (Ellen Pompeo) is the top candidate for the big prize. But more and more, Meredith is her mother, and the only thing that makes her her is her willingness to spring to action when a patient — any patient, but especially ones that look like people she loves — are in need, convenient timing or not.

Let's take it from the top, shall we?

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The episode begins with Meredith and Alex Karev (Justin Chambers) taking a ferry so that she can share the news of her nomination with Derek because that was always his spot. He is jealous, she reports — because of course he is. They only got to play the professional one-ups-manship game for just a little bit towards the end, but she's about to best him in the shiny prize category for sure now that she's gone full-on Ellis Grey mode at work. Perhaps the only surprise here is that she didn't just tell him via Post-It.

It's a good thing Zola understands her mother's endless ambition because even though she and Maggie (Kelly McCreary) have gotten all gussied up to be her dates to the ceremony, Mer's not eager to fly, which makes her decision to stick around once a big trauma rolls in that much easier for her. The two roller-coaster crash victims she attends to, a guy named Greg and a girl named Cleo, also just so happen to look like younger doppelgangers of George "007" O'Malley and Christina Yang herself ... and their pregnant friend is a dead ringer for Izzie Stephens in looks, personality and mannerisms, to boot. It's a freakish experience for Meredith, Alex, and Bailey (Chandra Wilson) to attend to these guys, but the resemblance to those who've since left this place makes them all the more eager to help them through.

The accident has also left one guy — who bears a strikingly close resemblance to Mark Sloan, with his grey hair and rugged handsomeness — with a bleeding brain, which gives Amelia Shepherd (Catarina Scorsone) something to replay beside the awkward moment she walked in on Owen (Kevin McKidd) having naked brunch with Karina DeLuca. No matter how good the french toast was, it's still not enough to erase the memory of that bizarre encounter.

She's perturbed to learn that Owen has taken the patient in for an operation without first running a scan on his brain because, hello, that's exactly how her brother died. And yes, that does contribute to her insistence that she'll bring the dang CT machine into the OR to get it done if needs be, but lo, the patient has a brain bleed that could cost him his life while Owen still stitches up his belly. Derek's still saving lives, even from six feet below (a "beat that, Mer!" moment for sure).

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Jackson Avery (Jesse Williams) does his best to coax her away from the scene so that she can go to the gala, where she's a shoo-in to win, but she declines. At first, it's because she's keeping Baby George's spine in place so he doesn't suffocate; then she's stitching up Yang Jr.'s abdominal bleed from a puncture wound.

Everyone's got other reasons to be emotional right now: Meredith's anxious about the awards show; Bailey's perturbed that Ben has been lying about his firefighting school pursuits; Alex is (probably) concerned about Jo (Camille Luddington)'s decision to expose her locale to her violent ex; and Arizona's very nervous about Sofia's return. But the presence of so many familiar faces, of people that meant so much to them, is amplifying the drama of these procedures.

Baby Izzie in particular seems to be hitting Alex hard, and Jo gives him all-out permission, if you can call it that, to touch base with her and see how she is, so he can put his mind at ease. But he refuses, citing his own imagined new life for her (which, perhaps not coincidentally, matches the real life of Katherine Heigl in many ways right now — e.g., living in a woodsy place with three kids). He doesn't want to know of anything else beyond what he's imagined.

As for Arizona (Jessica Capshaw), the reminder of Mark's face is actually encouraging because it's a source of strength and resilience and humor, and her impression of him is just spot on. As she rescues Baby Izzie's baby from the womb and saves mommy to boot, she's reminded of her own strengths as a mother and is finally ready to welcome her daughter back into her home, with Mark's big smile and cheery countenance on the brain again, just in the nick of time.

And Meredith, well, Baby Christina is just a sounding board for her own ambition. Not only does she consider Meredith and Jackson "surgical royalty," but she aspires to be her, much like Meredith and Christina were in awe of the top dogs in their intern days as well.

With all the good, sappy mojo of the evening, it's probably no surprise when Webber and Bailey decide to stream in the Harper Avery awards to Meredith's OR and her name is announced as the winner because good things are just happening right now in this season (well, until next week's big cyber attack, dun dun dunnnn). But what is a shocker is the moment when she looks up in the galley to see her cheering audience and finds the face of none other than Ellis Grey herself.

The transformation is complete. She has finally received the approval and admiration of her mother, and she knows it. If that moment doesn't raise all the gooseflesh on your skin, Grey's fans, nothing else will. Well, except maybe Christina Yang's congratulations call at the tail end there because, yes, they still do happy dance together, even half a globe away from one another.

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