Credit: Ron Tom/© 2011 Disney ABC Television Group Photo: Mark and Arizona Smile at the Baby Shower on Grey's Anatomy, March 24, 2011

This installment of Grey's AnatomySeason 7, Episode 17, "This Is How We Do It" to be exact — was filled with moments that left us breathless, especially in the last 15 minutes. In the highly unlikely event that you don't remember those, here's a breakdown of the thrills and chills.

Sonya & Son
This woman pulled herself out of Derek's trial just so her son Tariq could have a second shot with his ex in London instead of staying as her caregiver in Seattle. We're floored by this woman's sacrifice. She's practically handing her memory a death sentence just so her son could try to reunite with his ex. How selfless is that?

Owen's quandary
Bailey suggested that Richard delegate the task of choosing a new Chief Resident, and Richard did just that: he chose Owen as his proxy. When Cristina found out, she was elated, because she's married to the dude and he has to choose her. But then she realized the problem: for the sake of impartiality, he couldn't possibly choose her. Now that's a bitter pill to swallow.

Adele's breakdown
Adele passed the test, but just by one point — meaning she definitely has Alzheimer's but is ineligible for Derek's trial. That's some bitter irony... and some fine drama. (Props to Shonda & Co. for that twist.) But we were just lamenting the loss of the classic Grey's monologue, and here comes another — one that was acted to perfection by Loretta Devine. Derek, Meredith, and especially Richard were on the brink of tears, and we weren't far behind.

Arizona proposes
The formula isn't new to Grey's: in the midst of some serious drama, usually a brutal argument, a character does something brash and wildly romantic. And we're such suckers for it. In this case, Callie and Arizona were probably having one of their most vicious fights yet when Callie just went all in and proposed. But, in a one-two-punch of OMG-ness...

Arizona crashes
You shouldn't drink and drive. You shouldn't text and drive. And, may we add, you shouldn't propose and drive. Because you won't want to have to look at the road. You'll want to look in your loved one's eyes. And that's a problem. Suddenly, it became apparent why Callie would have a medical emergency in the forthcoming musical episode. But we forgot one crucial aspect until we saw the previews for next week: Callie was unbuckled at the time. We're nervous wrecks about this wreck.

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