Last night's Grey's Anatomy saw the world of Seattle Grace as we know it turned on its head. The Mercy Westers descended, wreaked havoc and one of our own got fired.

How long will Izzie Stevens be gone? Did she really leave Alex? These questions remain up in the air for now in the wake of her abrupt departure at the end of the episode.

Lexie, Alex and Cristina each did whatever they could to upstage their new Mercy West counterparts, with largely failed results. Our people are looking dazed and confused.

Elsewhere, Callie's dad returned to convert her, but he was the one who saw the light. Bailey's patient was almost killed by Izzie, driving her to L.A. and Private Practice.

For the full rundown of events last night, here's our recap of "Invasion."

Richard lets Izzie go. She does not take the news well.

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