Credit: Danny Feld/ABC Television Group © 2010 Disney Photo: Dr. Bailey on the Grey's Anatomy Musical Episode on March 31, 2011

Let's face it: this Grey's Anatomy musical episode — Season 7, Episode 18, "Song Beneath the Song" — was pretty much one giant OMG moment, but let's talk about the five moments that really surprised us and had us reaching for the rewind button.

5. Meredith's breakdown
Meredith's elevator confession that she was jealous of Callie's pregnancy was appalling at first and then heartbreaking. And it's a lesson for us all — to not focus on troubles that are relatively trivial... because you never know when a big truck full of pain is gonna wreck someone else's life.

4. "Breathe"
We knew beforehand that Sara Ramirez, Kevin McKidd, and Chandra Wilson had some serious pipes on them, but how much of a breath of fresh air was our Chyler Leigh? When she sang "Breathe (2 AM)" as Lexie went to find Mark, we were blown away. The girl was fantastic! When does her new album drop, anyway?

3. "Running on Sunshine"
This song was ridiculous. On one hand, it was sweet to see the characters singing to their special someones. Callie and Arizona? Sweet. Alex and Lucy? Sweet. Eli and Bailey? Sweet. Meredith and Derek? Sweet. Owen and Cristina, all over the kitchen? Hot. But things got a little wonky toward the end. Did Henry really pop Teddy up with a pelvic thrust? Yes. Was Lexie really singing to Mark and petting his hair? Yes. We're a little mystified.

2. "The Story"
Okay, we knew Sara Ramirez could sing, but holy cow. We were unprepared for this vocal tour de force. She sang with such unbridled power, vigor, and emotion; we're already chanting "Grammy Grammy Grammy." Bravissima, Ms. Ramirez!

1. Callie says "yes"!
Shoot, we should have seen this coming! To have Callie wake up and say yes to Arizona's proposal is so totally a Shonda idea. But still, we were taken by surprise. And a squeal of delight might have escaped our lips. Hey, let's keep that between us, okay?

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